Reboot Homey Bridge from within the Homey app (or in a flow even)

I agree there should be a soft reboot option for it, pulling the plug as the only possibility is quite odd

But your network problems are the main issue imho. Like Pro 2016-2019 models, Homey Bridge only likes a dedicated 2.4GHz wifi connection. There’s even a dedicated topic:

When it’s connected to one of several AP’s, make sure it isn’t allowed to roam.

Bind its IP address to its MAC address (“reserve IP address”).