Facetime call answered on new mac is not connected to calling phone

I just migrated to a new mac, and now when a call comes into my iPhone, it also pops up on the Mac (facetime - like it should) - HOWEVER when I answer on the mac - the call is never connected. The calling party just continues to hear ringing, or going straight to voicemail.

MAC os: 10.15.5

ios: 13.5. (but same behavior on all IOS's and non-IOS phones).