I changed my number, every time I am trying to text my girlfriend, it always converts to a group message with her, myself and my old phone number. She isn't receiving half of my message either. Sometimes they'll go through later and most get lost. I won't get most of hers either. But for some reason I am able to text all of my other friends/family with no problems! I was thinking of backing my apps and content to the Verizon cloud and factory resetting but I am skeptical it's even my phone. Though, this only started happening after I changed my number.