Recently my phone has been acting weird. I have an AT&T iPhone 6 and upgraded to iOS 9.3, I will have 2-3 bars of LTE and my phone won't load or send messages. When I open apps, Instagram, Facebook, Twitter, Safari, it says "offline mode" or "no service" I then have to turn on airplane mode and turn off airplane mode and my phone works again. Has anyone had this problem? Or know how to fix it? Thanks!