I'm not sure if this is the correct place to post this, but I purchased a used iPhone 7 and it seems like there was a balance on AT&T. It works fine on AT&T with any att sim- but I want to use it overseas in the next few weeks, and the only solution seems to pay someone on ebay $100 to remove the network lock. I tried a seller who charged $20 but it never worked. Does anyone know how these people do it? please pm me if you have any idea$ Thank you!