Try to isolate the issue to the specific handset by making sure that another Vote handset placed in the same spot is working correctly. If another Vote handset is working correctly on that same spot, then we have isolated the issue to the specific handset. Next, unscrew the Vote handset and check to see if the battery has become loose. If the battery is in place and the handset still has a blinking backlight, then contact Technical Support to inquire about an RMA.