I purchased a refurbished Samsung Galaxy S8 Active that was supposed to be unlocked but when I put my SIM card in, I got the MM6 error "Phone not allowed". After searching the internet to figure out the next step, I contacted the phone carrier AT&T, requested an unlock code, received the approval code and the only thing it said in my email instructions was to contact my carrier if I have additional questions. I Googled the Samsung instructions, followed them but still haven't gotten the prompt and I still have the same SIM code error.
I have MetroPCS which is owned by T-Mobile. They're not MVNO to AT&T according to my searches unless it's changed more recently since AT&T bought out T-Mobile. I should also add that I tried to do the dialer code and that didn't work either.
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