Unlocking a device

I transferred my line to T-Mobile from xfinity, and in the store I paid everything in full and I was told everything is unlocked. So I got the transfer pin and transferred everything to T-mobile. But at the last step I was told the e-sim cannot be activated because xfinity has a lock on it. I have spent my whole day trying to resolve this but I have been told it has been unlocked, we cannot unlock it because it has been disconnected, we created a ticket it should be done within 2-3 hours. Firstly if the number is locked why will you allow the transfer process? and if it is normal why can no body figure this out?