When i am texting a certain person on my Ally, and it only does it for this person...every 30 minutes or so, sometimes more, a pop up comes up that says "Message Received by 15555555555" (except it says that person's number). this pop-up usually only goes away if i turn the phone off and turn it back on. this gets very annoying, ive tried taking the battery out and everything. and i know i have delivery notifications for SMS turned off. does anyone know how to fix this? please help!