Hi @Liz808
Welcome to the Sonos Community!
Sorry to hear of the issues you’ve had with getting your Sonos system working on your new network.
Please be aware that your Beam is incapable of connecting to 5GHz WiFi - it reserves it’s 5GHz radio for communicating with Subs and Surrounds.. Any attempt to get your Beam to connect to 5GHz WiFi will fail. 2.4GHz must be used for the Beam instead.
Your surrounds and Sub will connect to the Beam rather than to the router once configured, so really, your Sonos system just want’s to be on 2.4GHz only.
I hope this helps.