I've been having a problem with my phone where a single number will not receive any text messages sent from my number. I receive any texts from him without any issue, and we can both call each other as well. I am on Verizon, an iphone 5 with the latest software (7.1). He is on AT&T with an android device. He does not and has never had an iphone on his account, so I know it's nothing to do with iMessage (I have turned iMessage on and off as well to no avail). We have both deleted groupme or other messaging systems that other help threads I've seen online blame as the problem. I have not had this problem with anyone else in my contacts, and it seems to have started out of nowhere.