iPhone 11 sim locked
I have a iPhone 11 that I bought off a guy the phone was still in the box and was told never used. I put my sim card in it and “sim not supported” shows up. I call apple and they couldn’t help me but tracked the phones Serial number to be a t mobile phone but never had service attached to it. So I go and call them up asking for a unlock request and they said it’s not possible because a account was never made with this phone but told me through the imei number that the phone is indeed unlocked. In setting under carrier lock it says sim is locked and am unable to use with my current provider.
please help me at least find a path in the right direction