Oppo,xiaomi,vivo devices don't show fcm flutter backround notification

Question

I am trying to send notifications from my app at certain times using Flutter Firebase Messaging. Notifications; The application does not appear when deleted from the background on OPPO, XIAOMI, VIVO .. devices. As far as I research my application is on the device because it is on the black list;

• User should activate autostart

• User should allow the app to run in the background

• User should add it as a priority application,

User need to make settings like that..

I don't think this is a good way. These features can change on every phone or all users may not be able to do them. So , is there any way to solve solution that problem or in what other ways I can send notifications to these devices, I am stuck on this issue for a few days, I would be very happy if you help.

Thank you very much for your time in advance. I wish everyone a good work ...

manifest.xml code;

    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="************">
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="oppo.permission.OPPO_COMPONENT_SAFE"/>
    <uses-permission android:name="com.huawei.permission.external_app_settings.USE_COMPONENT"/>
    <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />
   <application
       android:name="com.*****.Application"
        android:label="daisy_period_app"
        android:icon="@mipmap/ic_launcher">
       <meta-data
           android:name="com.google.android.gms.ads.APPLICATION_ID"
           android:value="ca-app-pub-3940256099942544~3347511713"/>
        <activity
            android:name="*************.MainActivity"
            android:launchMode="singleTop"
            android:theme="@style/LaunchTheme"
            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"

            android:excludeFromRecents="true"
            >
     
            <meta-data
              android:name="io.flutter.embedding.android.NormalTheme"
              android:resource="@style/NormalTheme"
              />
            <!-- Displays an Android View that continues showing the launch screen
                 Drawable until Flutter paints its first frame, then this splash
                 screen fades out. A splash screen is useful to avoid any visual
                 gap between the end of Android's launch screen and the painting of
                 Flutter's first frame. -->
            <meta-data
              android:name="io.flutter.embedding.android.SplashScreenDrawable"
              android:resource="@drawable/launch_background"
              />
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
            <intent-filter>
                <action android:name="FLUTTER_NOTIFICATION_CLICK" />
                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>
        <!-- Don't delete the meta-data below.
             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
        <meta-data
            android:name="flutterEmbedding"
            android:value="2" />
       <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationBootReceiver">
           <intent-filter>
               <action android:name="android.intent.action.BOOT_COMPLETED"></action>
           </intent-filter>
       </receiver>
       <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationReceiver" />
    </application>

</manifest>

build gradle;

    def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}
def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}
def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '1'
}
def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
android {
    compileSdkVersion 29
    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }
    lintOptions {
        checkReleaseBuilds false
        disable 'InvalidPackage'
    }
    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.smnway.daisy_period_app"
        minSdkVersion 16
        targetSdkVersion 29
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        multiDexEnabled true
    }
    buildTypes {
        release {
            // TODO: Add your own signing config for the release build.
            // Signing with the debug keys for now, so `flutter run --release` works.
            signingConfig signingConfigs.debug
            shrinkResources false
            minifyEnabled false
        }
    }
}
flutter {
    source '../..'
}
apply plugin: 'com.google.gms.google-services'
dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    implementation platform('com.google.firebase:firebase-bom:26.5.0')
    implementation 'com.google.firebase:firebase-analytics'
    implementation 'com.android.support:multidex:1.0.3'
    implementation "com.google.firebase:firebase-messaging:20.1.0"


}