Bambu A1 stopped connecting to my WiFi

My Bambu A1 has suddenly stopped connecting to my WiFi network. Last time I looked a few days ago it was connected and nothing has changed since then. I've restarted my router and the printer several times. I can see the WiFi network on my printer but it just says failed to connect. I've tried changing the WiFi channel on my router but that doesn't change anything. Every other device works fine with my router so I'm pretty sure it's the printer playing up.

Does anyone know how I can fix this? I'm disappointed in Bambu labs, it seems like such a strange issue to suddenly arise when I haven't updated it or anything like that.

PS. I wanted to post on the Bambu Labs forum but their sorry excuse for a website doesn't seem to allow creation of new topics. It's not a new account as I've had it for months now.