Connection times out after 15 minute

Hi all,
I have an older phone (but Android 11) as wall panel with HA Companion App and Fully Kiosk.
The problem is that the websocket connection of the dashboard times out after around 15 minutes. When the screen switches on after that, I see the usual dialog “Connection lost. Reconnecting…”, which takes 3-4 seconds to refresh the dashboard. I have already excluded Companion App from battery optimization and switched off doze completely on the phone. I’ve enabled persistent connection in the app, but based on debug logs, it seems there is a separate connection just for notifications and that stays active even after hours.
Is there any way to keep the dashboard connection alive for long time? A “wall switch” that needs a few seconds to work is a bit pointless.

In your user profile turn off automatically close connection.

Thanks for your response. I forgot to mention that I also disabled “Automatically Close Connection” and that also didn’t resolve the issue.

Does anyone have an idea what else I could try or how to debug the exact cause?

I have a Samsung tab A8 and I am running into the exact same issue. After 5 minutes, if the tablet wakes up, it reloads the dashboard.

Automatically close connection is off.

I have the exact same problem, does anyone have a solution to this problem ?

Same problem here. Seems to be an issue regarding frontend.

Same here, but this issue is new for me.
I have been using the Companion app for over a year but since one or two months it had constant cutouts and is pretty unresponsive unless you do a full app reload…