You would be doing a port I am not familiar with mint or how they do ports but in general you get your account info needed to port and at the new Cartier go thru the steps perhaps a text asking for pin and port should begin
Is your phone unlocked or are the codes you speak of the unlock codes? If your phone is unlocked, it's just as simple as having your number ported (or starting new service/new number with new carrier) and popping in the new carrier's SIM or activating the e-SIM. If you are trying to unlock your phone to switch, you should have received instructions on the unlocking procedure, which you have to follow exactly as you only get limited tries. If you are having a problem switching services, it's best to go into the store and have them assist you.
