Hey there sam_93,
Thanks for reaching out to Apple Support Communities. I understand you’re having issues connecting to Wi-Fi. It sounds like you’ve done some thorough troubleshooting so far and I’ll be happy to help with this.
It looks like you’ve done all the steps from the official article on this:
If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network
Just to verify, have you tried this with a different Wi-Fi network and get the same results? If so, go to Settings > General > Date & Time and make sure that is correct. Restart your iPhone and try once more:
Restart your iPhone
Make sure there is nothing that could be causing Wi-Fi interference:
Resolve Wi-Fi and Bluetooth issues caused by wireless interference
Let me know if this helps.