I purchased my S8+ directly from Samsung and as such, the T-Mobile SIM unlock app does not work. According to XDA:
"I was in the same boat as you. Went through T-Force on Twitter and seemed to have gotten a rep on the first go who understood the situation and submitted my IMEI number to the right place. Your IMEI number needs to be added to their "device distribution inventory system" and needs to be submitted to their highest level tech support, this allows the Device Unlock app think your phone came from T-mobile's inventory and will let the app unlock your phone."
Base line support chat technicians are of ZERO help and insist that the unlock needs to come from Samsung which is not the case.
Hopefully this catches the eye of someone in support with the ability to help me. The device is paid off and has been active with Tmobile for longer than 40 days.
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