Billing & Technical Issues? No Problem! AT&T Manager Here to Rescue You!
If the device is unlocked and you are trying to change the APN over to T-Mobile's network, the instructions for this will have to come from the manufacturer. They are not listed on AT&T's website or in the owners manual so they will need to be contacted.
Customer's Rule....I'll prove it!
If you have the correct apn settings from tmobile, then what errors are you experiencing? The more specific you can be the more likely I can guide you in the right direction
2 Private Answers