please help me network unlock

I have OnePlus 9 pro t mobile , I buy this phone in turkey , my problem is i have a problem , i think the phone i bought has network lock , no matter what i do i cant remove network lock , where should i write ? according to what they told me, can t mobile employees remove the network lock, can you help please, I don't live in the USA and my phone unfortunately only reads t mobile sim cards but I have the network lock please someone help