Recently, my LTE signal has completely disappeared. I've done every reset I can think of, but nothing seems to work. I have an Iphone 5 with AT&T. Has anyone else had this problem?
Just call AT&T - they will help you if it's an account setup issue. Sometimes they have the wrong info in their system, and LTE isn't enabled for your phone. If that's not the problem, then go to the Apple store and ask them to run a diagnostic on the phone.