IMEI PREVENTED WHY IF THE DEVICE WAS NOT PURCHASED WITH T-MOBILE?

Greetings! My name is Igor Araújo, I have an Iphone X cell phone IMEI number 35487609416139 here in my country of origin, BRAZIL. And today I was surprised by the impediment in my IMEI by United States - T-Mobile USA, Inc. I want to know the reason and the reason for blocking my device and I request that it be unblocked beforehand.