Porting out should not be this hard

I payed my bill in full.i own my phone so why is porting my number to different carrier so hard? It’s been 3 days an my phone is still locked…I was on with Xfinity for 3 hours yesterday a they claimed it was fixed.. well tell o says Xfinity is known for this…. Just unlock my [Edited: "Language"] phone.. i own the phone and my bill is paid… so why do I have a gray screen that says simprovider unlock code… already spoke with Tello….  The phone is still locked… it’s been 3 days of this [Edited: "Language"]