Hi, I have a Samsung Galaxy S4, and I went on a trip to England last week, I had airplane mode on the entire time to avoid roaming charges, but when I came back to the States and tried to turn it off, it wouldn't return to normal. It says that airplane mode will be disabled, but I can't get any signal, even with WiFi. I've restarted the phone 3 times and pulled the battery twice, but the problem persists. Help, please!!!!!!!!!!!!!!