Apple Watch Ultra3 Activation

The watch will not activate. When I try to add the IMEI it says it is not compatible with the network. Which is not correct. They added the watch then it disappeared. I have gone through 4 chat sessions. 2 calls with the business Xfinity Mobile Executive Resolutions,. I am still waiting for the IT team to call me three weeks later. Recently the watch was cancelled then brought back. I was told on the chats that it would be fixed in 30 minutes each time. The team is disorganized and irresponsible with lack of communication between resolutions and tickets. I have several of them. Xfinity team members close them without solving my problem. Month 3 and several more phone calls. Does anyone know if the notice of dispute help?