Android resource linking failed while using braintree library

Question

I'm currently integrating Braintree in our project. But At the starting point, I'll use Braintree SDK in our project file the show Android resource linking error. error: resource android:attr/fontVariationSettings not found. error: resource android:attr/ttcIndex not found. error: failed linking references.

please let me know how to resolve the issue. Don't forget to share your answer

    **apply plugin: 'com.android.application'

android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.example.cz.paypal_intergration"
        minSdkVersion 21
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    implementation 'com.paypal.sdk:paypal-android-sdk:2.14.2'
    implementation 'com.braintreepayments.api:braintree:2.+'
}
**

Answer 1

compileSdkVersion 27 to 28 and targetSdkVersion 27 to 28

Answer 2

Update your compileSdkVersion 27 to 28