do this it should sort it
Performing a factory reset using the phone buttons
Remove the battery, wait for a few seconds, then reinsert the battery.
Press and hold the VOLUME DOWN button, and then briefly press the POWER button.
Wait for the screen with the three Android images to appear, and then release the VOLUME DOWN button.
Press VOLUME DOWN to select FACTORY RESET, and then press the POWER button.
WARNING!!! Factory Data Reset will permanently delete all your data and customized settings, and will remove any applications you’ve downloaded and installed. Be sure to back up any data and files you want to keep before you do a factory reset.