We have had a Outdoor Cam Plus on our rear deck and a Spotlight Cam Pro on our front deck for 3 months. Setup was easy, app worked flawlessly, connected to wifi reliably via Telstra Smart Modem on the NBN. Telstra just recently upgraded us to a 5G Smart Modem, and our rear deck camera connected first time, but the front (The Spotlight Cam Pro) will not. Have rebooted and reset the camera, changed the SSID and password on the new router to that of the old one, rebooted the router, downgraded WiFi-7 (802.11b/g/n/ax/bx) to 6, turned off band steering, set up a guest network with 2.4ghz,  security is set at WPA2/WPA3 (no option to choose only WAP2) - what else can I do?

I successfully connected the camera using my hotspot, so I know the camera is working. And the wifi is working, because the other Ring camera is connected and working! I deleted the Ring app and reinstalled it. Again no change and no connection.

Why is this so hard? Please help, before I give up completely and return it altogether!