Sorry to be dumb, when you said “goes off, and the other goes completely off” did you mean wifi disconnect off or power off and reboot?

If the device reboots then there’s a power issue. If the WiFi cuts out and kicks everything offline then it’ll be a configuration or hardware issue.

Nobody likes to have to reset hardware but it is honestly the best way to go when you can’t find the issue as it gives you a starting point.