If you notice that your light is shutting off after 10-15 seconds the most common cause is due to using an IPhone 11S Pro Max. These devices require a new, custom adapter which we are sending out for free to those that use this model. Please contact us if you have this device and it is shutting off. We currently offer 4 USB options with the kit so you can use any other device in the mean time while you whiten your teeth ( laptop, charging cube, tablet, etc. )In the rare event you aren't using this model and it is shutting off, please contact us!:) We have a 2-year warranty for our light and we will ship you a new light within the same day.Contact: business@novashinesmile.com