Do you use a Bluetooth keyboard with the iPad? If so, turn it off and turn Bluetooth off as well. Turn off any other Bluetooth devices within range of the iPad if you need to.
if that's not the problem, reboot the iPad.
Reboot the iPad by holding down on the sleep and home buttons at the same time for about 10-15 seconds until the Apple Logo appears - ignore the red slider - let go of the buttons.