I had the sam problem. I posted this on its own chat with heading "Loses Connection" last week Sunday, but nobody has responded.
Hi everyone. I dont know if this has been asked before, I have just joined the Discord server. For the last 2 weeks or so, Home Assistant runs smoothly for a few hours and then its like it just loses connection to everything. I can log into it on the app and web, but when trying to control anything it gives an "Failed to perfom the action switch /turn_on. network error:(-9999999) sign invalid. The automations also does not work when it goes into this "state". I am running it on UTM VM on a Mac Mini. Also, when trying to restart it in this state does nothing. I have to physically stop the VM an start it again. Then it works for a couple of hours and then does the same.
Specs:
Core 2025.3.4
Supervisor 2025.03.3
Operating System 15.0
Frontend 20250306.0
Any idea why this is happening and what the fix is?
Edit: I have loaded a backup version 14.1 back on the VM and it works perfectly. How does one report this bug to the developers?