I have a basic GT-E1200 mobile phone which has now become erratic in operation.It may be just faulty. When I now switch on, it appears to function normally for a few seconds, then if I try to make a call, it tells me the keyboard is locked. I have it set to unlocked. Then if I press to unlock it, I get a message "emergency calls only". Also if I click contacts, I get a message "loading" and then it switches itself off. When I switch on again and click menu/messages, I get the same result. Anyone any ideas to rectify please?