Wifi dropouts

Hello,

I’m running volumio on rasp pi 4b with Allo digiOne signature piggy back board.

I access Volumio via my smart phone browser. This is done via wifi and the wifi router is literally 0.5 m away from the rasp pi.

What I’m funding is after say an hours listening I cannot connect to the rasp pi via wifi as the browser reports volumio has dropped. It’s as if the rasp pi stops communicating with the wifi router. I can still access other web pages on the phone. Any ideas please.