2 of 2 people found this helpful
One important question is, where are you located? If you are in a border area (e.g. El Paso, Niagara Falls), your phone could be trying to access an international roaming partner. There may be a few locations in the US where you could be switching back and forth between T-Mobile and a domestic roaming partner. I would suggest turning your data roaming off and manually selecting T-Mobile to see if that cures the problem.