You could probably have some dust in the remote or the connections to the battery are not contacting. Check any lose connectors. If you have a video camera, you can aim the remote towards the camera lens and try pushing some buttons. Look through the camera LCD screen to see any infra-red signals out of the remote.
We don't have extra Fortec 786NA remotes available for sales right now but we are expecting a shipment soon. We could also program a
universal remote and send it to you if you need something urgent.