I have a Tablet running Android 2.2.It has been running great for almost 1 year but recently the touchscreen started to play up.I press an icon for an app and it opens a different one. On the keyboard all the letters have reversed from side to side. eg. If I press a letter 2 from the right the letter on that row 2 from the Left is written. When I switch the tablet on it comes up with the calibrate screen first and after successfully pressing the x it wont allow me to calibrate any more of the screen.on the two top corners. What can I do about it?