unlock phone

Hello - I have switched my family plan of 4 lines from Xfinity Mobile to a different carrier (Verizon) recently with number portability and am now stuck with a Xfinity locked iPhone XS Max 11 phone (mine) while the other one in the plan that was locked was successfully unlocked. It turns out that my iPhone has a different IMEI from the one that the Xfinity store offered initially since I had to take the original phone to Apple Store for a cracked screen that was still under warranty and so Apple had replaced my device with a new one. Xfinity says that the new IMEI is not registered to their Xfinity Account and they are struggling to have the new IMEI added/registered to my Xfinity account to have my phone unlocked. The problem apparently is because my number has already been ported over to Verizon. It's been almost 3 weeks since I switched to Verizon but neither am I able to switch to Verizon nor able to have my phone unlocked with Xfinity. Come on Xfinity - it can't be that hard to have a simple device unlock processed!! And it doesn't seem to be a rocket science problem either and there should be an easier and smoother way to handle this problem. Anyone has any ideas?? Because I am stuck in the middle here running from pillar to post to get my phone unlocked by Xfinity for the last 3 week!!