My Moto G phone just told me that I have an invalid card and says that I've used 20GB of data (which is not true). I was visiting my family on a boarder city for a week. Drove through the states to get home (put it on airplane mode while in the US). Used it when we got back in the country. And then this evening, got the phone lock. We haven't used it anyway out of the ordinary. What do I do?