This Activity already has an action bar supplied by the window decor. not solvable with AppTheme

Question

Yeah as you can see above I get the mentioned Error. But I'm 100% sure the Activity's theme doesn't have an Action Bar. I'm trying to get de Toolbar working but every time I open the Activity the App crashes.

Here is the full Stacktrace

2019-12-10 22:32:54.796 27068-27068/com.simplemobiletools.studentcalendarpaid.debug E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.simplemobiletools.studentcalendarpaid.debug, PID: 27068
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.simplemobiletools.studentcalendarpaid.debug/com.simplemobiletools.studentcalendarpaid.activities.MainActivity}: java.lang.IllegalStateException: This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3047)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3182)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1916)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:193)
        at android.app.ActivityThread.main(ActivityThread.java:6898)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:537)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
     Caused by: java.lang.IllegalStateException: This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.
        at androidx.appcompat.app.AppCompatDelegateImpl.setSupportActionBar(AppCompatDelegateImpl.java:345)
        at androidx.appcompat.app.AppCompatActivity.setSupportActionBar(AppCompatActivity.java:130)
        at com.simplemobiletools.studentcalendarpaid.activities.MainActivity.toolBar(MainActivity.kt:192)
        at com.simplemobiletools.studentcalendarpaid.activities.MainActivity.onCreate(MainActivity.kt:178)
        at android.app.Activity.performCreate(Activity.java:7149)
        at android.app.Activity.performCreate(Activity.java:7140)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1288)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3027)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3182) 
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1916) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loop(Looper.java:193) 
        at android.app.ActivityThread.main(ActivityThread.java:6898) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:537) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858) 
2019-12-10 22:32:54.800 27068-27068/com.simplemobiletools.studentcalendarpaid.debug W/OPDiagnose: getService:OPDiagnoseService NULL
2019-12-10 22:32:54.817 27068-27068/com.simplemobiletools.studentcalendarpaid.debug I/Process: Sending signal. PID: 27068 SIG: 9

Here you can see the main Activity

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(com.simplemobiletools.studentcalendarpaid.R.layout.activity_main)
        appLaunched(com.simplemobiletools.studentcalendarpaid.BuildConfig.APPLICATION_ID)


        prefs = getSharedPreferences("com.simplemobiletools.studentcalendarpro", MODE_PRIVATE);
        prefs = getSharedPreferences("com.simplemobiletools.studentcalendarpro", MODE_PRIVATE);


/*
        prefs = getSharedPreferences("com.simplemobiletools.studentcalendarpro", MODE_PRIVATE)
        if (prefs!!.getBoolean("firstrun", true)) {
            val h = Intent(this@GradeMainActivity, OnBoardingActivity::class.java)
            startActivity(h)
            prefs!!.edit().putBoolean("firstrun", false).apply();
        }
*/





        drawerLayout = findViewById(com.simplemobiletools.studentcalendarpaid.R.id.drawer_layout)
        navigationView = findViewById(com.simplemobiletools.studentcalendarpaid.R.id.nav_view)
        navigationView!!.bringToFront()


        navigationView!!.setNavigationItemSelectedListener(this)

/*
        val toggle = ActionBarDrawerToggle(this, drawerLayout, toolbar,
                R.string.navigation_draw_open, R.string.navigation_draw_close)
        drawerLayout!!.addDrawerListener(toggle)
        toggle.syncState()
*/
/*
        checkWhatsNewDialog()
        calendar_fab.beVisible()
        */
        calendar_fab.setOnClickListener {
            launchNewEventIntent(currentFragments.last().getNewEventDayCode())
        }
       storeStateVariables()
        if (resources.getBoolean(com.simplemobiletools.studentcalendarpaid.R.bool.portrait_only)) {
            requestedOrientation = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT
        }

        if (!hasPermission(PERMISSION_WRITE_CALENDAR) || !hasPermission(PERMISSION_READ_CALENDAR)) {
            config.caldavSync = false
        }

        if (config.caldavSync) {
            refreshCalDAVCalendars(false)
        }

        swipe_refresh_layout.setOnRefreshListener {
            refreshCalDAVCalendars(false)
        }

        if (!checkViewIntents()) {
            return
        }

        if (!checkOpenIntents()) {
            updateViewPager()
        }

        checkAppOnSDCard()







        updateViewPager()



        toolBar()

    }


    private fun toolBar() {
    val  tb = findViewById<Toolbar>(R.id.myToolbar)
    tb.setTitle("Android Toolbar");
    // tb.setTitleTextAppearance(this, R.style.toolbarTitle);
    // tb.setSubtitle("My SubTitle");
    // tb.setSubtitleTextAppearance(this, R.style.toolbarSubTitle);
    // tb.setContentInsetsAbsolute(0, 54); // Best used when setting a Logo
    // tb.setContentInsetsRelative(0, 54); // Best used when setting a Logo
    // tb.setLogo(R.mipmap.ic_launcher);
    setSupportActionBar(tb)

        if (getSupportActionBar() != null) {
      // This sets a shadow underneath the Toolbar
        getSupportActionBar()?.setElevation(8F);
        }
    }



    override fun onNavigationItemSelected(item: MenuItem): Boolean {
        // Handle navigation view item clicks here.
        // here is the main place where we need to work on.
        val id = item.itemId
        when (id) {

            com.simplemobiletools.studentcalendarpaid.R.id.nav_calendar -> {
                val h = Intent(this@MainActivity, MainActivity::class.java)
                startActivity(h)
            }
/*
            com.simplemobiletools.studentcalendarpro.R.id.nav_account -> {
                val l = Intent(this@GradeMainActivity, AccountActivity::class.java)
                startActivity(l)

            }*/
            com.simplemobiletools.studentcalendarpaid.R.id.nav_todo -> {

                /*Falls ich Fragments gebrauchen will
                //val fragment = ToDoFragment()

                //displayFragment(fragment)
                //supportFragmentManager.beginTransaction().add(R.id.fragments_holder, fragment).commitNow()

                    */


                val m = Intent(this@MainActivity, TodoActivity::class.java)
                startActivity(m)

            }


                R.id.nav_grades -> {
                val i = Intent(this@MainActivity, AddGradeActivity::class.java)
                startActivity(i)
            }

            com.simplemobiletools.studentcalendarpaid.R.id.nav_info -> {

                val k = Intent(this@MainActivity, com.simplemobiletools.studentcalendarpaid.activities.InfoActivity::class.java)
                startActivity(k)
            }
            com.simplemobiletools.studentcalendarpaid.R.id.nav_overview -> {
                val j = Intent(this@MainActivity, ViewListContents::class.java)
                startActivity(j)

            }


        }// this is done, now let us go and intialise the home page.
        // after this lets start copying the above.
        // FOLLOW MEEEEE>>>
        val drawer = findViewById<View>(com.simplemobiletools.studentcalendarpaid.R.id.drawer_layout) as DrawerLayout
        drawer.closeDrawer(GravityCompat.START)

        return true

        updateViewPager()
    }


    private fun displayFragment(fragment: Fragment) {
        supportFragmentManager
                .beginTransaction()
                .replace(R.id.fragments_holder, fragment)
                .commit()
    }

and here my styles.xml

<resources>

    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">

    <item name="windowActionBar">false</item>
    <item name="windowNoTitle">true</item>


</style>

    <style name="AppTheme2" parent="Theme.AppCompat.Light.NoActionBar">
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">true</item>
    </style>

    <style name="AppTheme.NoActionBar">
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">true</item>
    </style>


    <style name="SplashTheme" parent="Theme.AppCompat.Light.NoActionBar" >

    </style>
    <style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />


    <style name="TextAppearance44">
        <item name="android:textColor">#ffff</item>
        <item name="android:textSize">16sp</item>
    </style>


    <style name="AppTheme1" parent="Theme.AppCompat.Light.NoActionBar">
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">true</item>




    </style>

    <style name="AudioFileInfoOverlayText">
        <item name="android:paddingLeft">4px</item>
        <item name="android:paddingBottom">4px</item>
        <item name="android:textColor">#ffffffff</item>
        <item name="android:textSize">12sp</item>
        <item name="android:shadowColor">#000000</item>
        <item name="android:shadowDx">1</item>
        <item name="android:shadowDy">1</item>
        <item name="android:shadowRadius">1</item>
    </style>



    <style name="AppTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" />

    <style name="DayView">
        <item name="android:gravity">center</item>
        <item name="android:textSize">@dimen/day_text_size</item>
        <item name="android:fontFamily">sans-serif-light</item>
    </style>

    <style name="MetaView" parent="DayView">
        <item name="android:textStyle">bold</item>
        <item name="android:textSize">@dimen/meta_text_size</item>
    </style>

    <style name="WeekNumberStyle">
        <item name="android:textStyle">bold</item>
        <item name="android:gravity">top|center_horizontal</item>
        <item name="android:textSize">@dimen/day_monthly_text_size</item>
        <item name="android:textColor">@color/default_text_color</item>
        <item name="android:fontFamily">sans-serif-light</item>
    </style>

    <style name="ArrowStyle">
        <item name="android:background">?android:attr/selectableItemBackgroundBorderless</item>
    </style>

    <style name="MonthStyle">
        <item name="android:background">?android:attr/selectableItemBackground</item>
    </style>
</resources>

and here the important thing in my Main Application

   toolBar()

    }


    private fun toolBar() {
    val  tb = findViewById<Toolbar>(R.id.myToolbar)
    tb.setTitle("Android Toolbar");
    // tb.setTitleTextAppearance(this, R.style.toolbarTitle);
    // tb.setSubtitle("My SubTitle");
    // tb.setSubtitleTextAppearance(this, R.style.toolbarSubTitle);
    // tb.setContentInsetsAbsolute(0, 54); // Best used when setting a Logo
    // tb.setContentInsetsRelative(0, 54); // Best used when setting a Logo
    // tb.setLogo(R.mipmap.ic_launcher);
    setSupportActionBar(tb)

        if (getSupportActionBar() != null) {
      // This sets a shadow underneath the Toolbar
        getSupportActionBar()?.setElevation(8F);
        }
    }

Here is also my Manifest.xml

 <activity
            android:name="com.simplemobiletools.studentcalendarpaid.activities.MainActivity"

            android:theme="@style/AppTheme2"

            android:launchMode="singleTask">
            <meta-data
                android:name="android.app.default_searchable"
                android:resource="@xml/searchable"/>


            <intent-filter>
                <action android:name="android.intent.action.SEARCH"/>
            </intent-filter>

            <intent-filter>
                <action android:name="android.intent.action.VIEW"/>
                <category android:name="android.intent.category.DEFAULT"/>

                <data android:scheme="content"/>
                <data android:scheme="file"/>
                <data android:mimeType="text/x-vcalendar"/>
                <data android:mimeType="text/calendar"/>
            </intent-filter>

            <intent-filter>
                <action android:name="android.intent.action.VIEW"/>
                <category android:name="android.intent.category.DEFAULT"/>

                <data android:mimeType="time/epoch"/>
                <data android:host="com.android.calendar"/>
                <data android:scheme="content"/>
            </intent-filter>

            <intent-filter
                tools:ignore="AppLinkUrlError">
                <action android:name="android.intent.action.VIEW"/>
                <category android:name="android.intent.category.DEFAULT"/>
                <data android:mimeType="vnd.android.cursor.item/event"/>
            </intent-filter>
        </activity>

As you can see I set the AppTheme to NoActionBar and still get this Error: This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.

Does somebody know the answer?