Under the device settings menu you may perform a three point touch-screen calibration by pressing and holding the yellow squares until they turn green when prompted, and then hit the back button when done to save the newly calibrated values.
If your Model-T is so out of calibration that you can't navigate to the touchscreen calibration menu above, factory default touchscreen calibration can be restored by pressing and holding the screen anywhere for 30 seconds and then following the directions on the screen.
NOTE: This press and hold action must be initiated within the first 30 seconds of powering on the Model-T, so you may need to power cycle the unit.