Peer to Peer Communication

I have a Nokia Gateway and I am unable to use my HomePods as a sound system for my AppleTv because of the lack of peer to peer communication. I have even reset them twice. They would work for a while and then misbehave.

Is anybody able to use this feature? Is it a gateway issue (works on other brands) or a network issue?

Also, if I enable “Add Wi-Fi Calling for Other Devices”, Wi-Fi calling turns off in seconds. I have not connected this to the T-Mobile network until I reinstalled the cable modem and everything works like a charm, including the HomePods.