App Lock displays blank screen

I have been using AVG Pro for Xperia for several years. Latest version 6.9.2.  So now I've purchased a new Huawei P20 lite and brought all my apps over from the Xperia. Everything AVG works fine except the App Lock, one of my favourite features.  It's  set up to use a pin code to unlock the App but when I open a locked app I just get a blank screen.

Any ideas or suggestions would be welcomed.

Hello David,

We’d be happy to help get your AVG working like it should. I have sent you an email, please provide the proof of purchase of your AVG PRO for Xperia subscription to locate the details and assist further.

Hello David,

We’d be happy to help get your AVG working like it should. I have sent you an email, please provide the proof of purchase of your AVG PRO for Xperia subscription to locate the details and assist further.