I am trying to take READ_EXTERNAL_STORAGE permission from the user for my music player app but its not showing any pop up for permission

  Dexter.withContext(this)
                .withPermission(Manifest.permission.READ_EXTERNAL_STORAGE)
                .withListener(new PermissionListener() {
                    @Override
                    public void onPermissionGranted(PermissionGrantedResponse permissionGrantedResponse) {
                        Toast.makeText(MainActivity.this, "Permission Granted", Toast.LENGTH_SHORT).show();
                    }

                    @Override
                    public void onPermissionDenied(PermissionDeniedResponse permissionDeniedResponse) {
                        Toast.makeText(MainActivity.this, "Permission Denied", Toast.LENGTH_SHORT).show();
                    }

                    @Override
                    public void onPermissionRationaleShouldBeShown(PermissionRequest permissionRequest, PermissionToken permissionToken) {
                        Toast.makeText(MainActivity.this, "Permission Rationale Should Be Shown", Toast.LENGTH_SHORT).show();
                    }
                })
                .check();

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

  implementation 'com.karumi:dexter:6.2.2'

I am trying to take READ_EXTERNAL_STORAGE permission from the user for my music player app but its not showing any pop up for permission