If nobody would do it. Why would company offer it? If it was indeed an anti-theft company should have informed the original owner(in their record) and should have denied any unlocking. If it was real anti-theft why would they provide app to unlock carrier.
Let me give you an example of actual anti-theft feature.
Apple will not unlock iPhone, no matter how much money u try to pay. That's an anti-theft feature. T-MOBILE has history of excess charging customers. This is plain & simple business tactics to earn more money. As OP @Charger8232 told T-Mobile's official app is dysfunctional. That app is dysfunctional, so people can't unlock themselves.