I'm contantly texting my girlfriend on her AT&T phone from my Verizon phone. For the past month or so I will sometimes not receive texts that she sends to me. Sometimes it happens with 1 out of every 20 texts, and other times it will happen with 3 texts in a row. It seems that the problem has been getting worse as time goes on, and I really have no idea what could be causing it or what to do, so any help/advice on what to do would be greatly appreciated.