The device isn’t automatically restarting.
In the Quell App, go to Settings and Therapy Dose. If "Manual" is selected, you will need to manually restart therapy. With any other selection (Regular, Low, or High Dose), therapy will automatically restart as long as the device is attached to your leg and all 4 gel pads on the electrode are making complete contact with your skin. Therapy may also need to be manually restarted if your last therapy was manually stopped, your last therapy was halted due to unsnapping, you calibrated your device since your last therapy or you charged your device since your last therapy session.
If desired, you can set your device to start therapy automatically when you attach it to your leg. Open the Settings menu on the app, select the Therapy Automation, and enable “Automatic Start”. This setting enables the device to begin therapy automatically within one minute of placing the device on your leg. When enabled, you do not need the app to start therapy.