Can't connect iWatch Series 6 to AT&T cellular plan

I have had this phone and watch since March 2021 for my son and I can't get the cellular to connect on the watch. I have AT&T and when I go to set up the cellular on it I get an error message that has no error code. It just tells me that the connection failed and wont log in to AT&T. I have sent the watch to Apple twice for repairs, I have contacted AT&T several times and escalated it as well and I am still having the same issue. So I completely unpaired the watch from my sons device(iPhone 12 mini) and tried to set it up as a family member from my phone directly. I finally got it to give me an error code. It says that the eSim has been deleted or is missing with the code being EDS4100. It then tells me to contact Apple Watch Tech Support for a new one. I did that and they say its on AT&T's side. Ugh.... anyone have any suggestions or solutions? The first image is the error I get when trying to connect cellular to the watch on my sons phone and the second image is the error I get when trying it on my phone.