Just like Cricket did, you go to the new carrier's counter and ask them to try.
This question had been asked many times. Be sure to review prior answers.
Bob
Is there a way to unlock a Galaxy S4 CDMA?
I got it from Cricket a year ago and was with them for one year and went to another carrier with a new S5.
It has an IMEI number starting with 99.
I have learned a lot just trying to unlock this thing but the farther I go the worse it gets, it's a great phone and it would be a shame if I couldn't sell it.

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