Trouble connecting Octopi to wifi

What is the problem?

When I write Octopi to SD card and conficure the wifi details in the supplicant document, I put the sd card in the Raspberry pi 4. It connects fine and gives me an IP. I set up octoprint. I then switch it off. When I turn it back on again, I get no IP to connect to. It only seems to offer one chance to connect, straight after a fresh build. Once it is powered off and turned on again I can't connect.

What did you already try to solve it?

I have tried rebuilding, adding to reserve list in DHCP

I have exact same issue. I shut down the Pi4 with sudo halt. Pi boots back up & I can log in but it fails to see network, and I can't PuTTY in from Win 11.and cannot use Octoprint on my Prusa.

I checked with my network provider to see if the router can see the Pi and it doesn't. I have rebooted router. Still cannot connect.

Can someone please provide some clues?