Lat night my ability to send texts just stopped. I'm able to receive them, but not send them. Any text I tried to send after 8pm last night have not gone through. It LOOKS like they did, but the date and time stamped on the text is whatever the current time is. Also last night the phone froze completely. I couldn't turn it on, off, change screens, nothing. Then suddenly around 11 it was on, and I could do everything EXCEPT send texts. When I was able to turn it off then on again, I get this message on the screen: "Currently unable to send your message. It will be sent when the service becomes available." Why can I receive but not send if the service is unavailable???