setup error 300252

I reset the HomePod several times, but not the home app. However I found my solution. I tried to add to a different room and it worked. after it was setup again, I moved it back tot he other room. odd. but works again now

Not sure I truly understand. The HomePod mini was connected and working fine for months. It just stopped connecting to my home app today. I restored it, now trying to setup again and it gives me that error. Im on WPA-2 personal (again worked fine before) - went through all my modem security settings and couldn't find anything mentioning the other things you said (client/access point/wireless isolation/security feature)