Android V12 frequent disconnect

I use the android version to easily connect to my 80 year old mother's phone to help her out. Over the past few weeks it will connect, I can see her home screen, but loses connection and doesn't reconnect. We have both installed and reinstalled and it keeps happening.

I'm panicked she will be out somewhere and I won't be able to access her phone and help her, especially with Uber that she uses to get around.

Any help would be greatly appreciated.

Thanks