android app closes (not crashes) after taking runtime permission for storage and audio

My app closes right after I allow permissions for external storage and audio and resumes from there when I open it next time. It is happening in an actual(real) device but works perfectly fine on the AVD. I have used dexter library for taking permissions.

Here is the code-

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listView=findViewById(R.id.listView);

        runtimePermission();

    }

    //method to take the permission from the user to access external storage; if granted run displaySongs() method
    public void runtimePermission()
    {
        Dexter.withContext(this).withPermissions(Manifest.permission.READ_EXTERNAL_STORAGE,Manifest.permission.RECORD_AUDIO).withListener(new MultiplePermissionsListener() {
            @Override
            public void onPermissionsChecked(MultiplePermissionsReport multiplePermissionsReport) {
                displaySongs();
            }

            @Override
            public void onPermissionRationaleShouldBeShown(List<PermissionRequest> list, PermissionToken permissionToken) {
                permissionToken.continuePermissionRequest();
            }
        }).check();
    }

Here are the permissions in Manifest

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO"></uses-permission>

The closing of the app after giving runtime permissions after installing it on a device for the first time gives an annoying experience.Hope anyone could help me with this.