I am trying to calibrate but I don’t feel anything.

Confirm electrode liner has been removed and that the lights have been running back and forth for at least 30 seconds. The purpose of the calibration process is to measure your sensation threshold, meaning that when you feel even the slightest sensation, you should click the button. Do not wait until the sensation feels very strong to click the button. It may take 20-30 seconds to feel the sensation the first time and the sensation may feel very light. You will feel subsequent stimulation slightly faster. If you go through the calibration process and never feel stimulation (or press the button), the therapeutic intensity will be set at the maximum possible intensity