Enabling Wifi-Calling on iPhone 14 Pro Max

I purchased an iPhone 14 Pro Max from Xfinity Mobile last November. Despite having had the phone for 9 months, I have been unable to activate wifi calling with Xfinity's assistance. I have spent roughly 80 hours on the phone with their tier 3 and 4 support team, but it seems that most of them are unfamiliar with wifi calling. They have repeatedly advised me to perform a network reset, which has not resolved the issue. Additionally, they suggested that I go to Apple and have my phone checked for wiring problems. However, after Apple tested everything and even installed another carrier's eSIM, the phone worked perfectly fine. The problem lies solely with Xfinity's eSIM/network. Anyone who sees the error message that appears when I try to enable wifi-calling would immediately recognize that it's an issue with Xfinity. Unfortunately, the Xfinity Mobile service has been a complete disappointment and a scam. I'd urge Xfinity to fix the problem immediately or take back the phone and cancel my line.