1. Hold power button down to power off. 

2. Wait 5 - 10 seconds before repowering back on with the power button. 

3. If that doesn't work, power off the printer with the power button and unplug the printer from the wall.

4. Wait about 20 seconds before plugging the printer back in and repowering back on with the power button.

5. If this doesn't work please reply or submit a ticket. Thank you.