<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.reactnativenavigation">

    <application
        android:theme="@style/Theme.AppCompat.Light.NoActionBar">
        <activity android:name=".controllers.NavigationActivity" />
        <activity
            android:name=".controllers.PortraitNavigationActivity"
            android:screenOrientation="portrait" />
        <activity
            android:name="com.facebook.react.devsupport.DevSettingsActivity"
            android:exported="false" />
    </application>

</manifest>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.reactnativenavigation">

    <application>
        <activity android:name=".controllers.NavigationActivity" />
        <activity
            android:name=".controllers.PortraitNavigationActivity"
            android:screenOrientation="portrait" />
        <activity
            android:name="com.facebook.react.devsupport.DevSettingsActivity"
            android:exported="false" />
    </application>

</manifest>

Remove conflicting theme property from Application
Remove conflicting theme property from Application
