Android app requires constant reboot

I tried searching for this, but found nothing yet I cannot believe I’m the only one with this problem. Anyway, I’m using the Android App on my Samsung J2 phone. It takes what seems like a long time to boot initially, but I can live with that. The real problem is that every time the screen blanks or I open a different app, when I return to Volumio it is frozen. As in NOTHING works. I have to close the app and reopen it (thankfully it is faster after the first boot). This is annoying always, but really a pain if the house phone rings and I want to turn the volume down or pause playback.
Any suggestions or help appreciated!

Same here on Oppo Reno 10x Zoom

Verstuurd vanaf mijn CPH1919 met Tapatalk

Energy saver app service on android?

I checked and ‘Battery Maximizer’ is definitely turned off.