New Mac Studio Won't Connect to Wifi

Hello,

I recently bought a Mac Studio and used Migration Assistant to move everything from my 2017 Intel Mac over to the new computer.

Everything was fine apart from the fact that it wouldn't connect to wifi. The wifi symbol would say it was connected but whenever I tried to use internet/email/App Store etc it would say "wifi not available".

I spoke to Apple Support numerous times and we tried loads of things - reinstalling, changing the DNS settings - and nothing worked. (Although, it did actually work in Safe Mode). In the end, we agreed that I'd send the Mac Studio back and they would send another one out.

Unfortunately, I have the exact same problem with the replacement. So clearly, the problem is somehow with my end - but I don't know what. Before I go through the whole caboodle with Apple Support again, does anyone here have any suggestions?

Thanks!