Octavia 3 canton soundsystem

Hello,
I have weird behavior in my car
I have Octavia 3 1,4 tsi (10/2013) elegance with canton sound system.
I noticed that in latest scans module 47 - amplifier was gone.
After enabling it I get errors
Module 19 - Malfunction
and module 47 - can not be reached
Result is like this when doing autoscan.
When accessing modules itself, then 47 connects fine and shows no error codes.
Module 19 still shows error code and this can not be cleared.
So clearly there is something wrong
Module 47 disappeared between scans at 22.04.2019 at mileage 165584km and 15.06.2019 at 169302km

Is it possible that car will un-tic a module from installed list by itself when communication is lost for long time or does it have to be done manually?
I did have cam belt change done between those mileages and dates so it is possible that some one could have tampered with software.

Any advise, what to do next to get the errors sorted?