Problem with fire stick

I am trying to setup a 4K fire TV (stick) with my Sofabaton U1 remote.  I had it connected, to the fire stick (fire TV) and was making some changes and had a problem. I had the Fire TV forget the U1 remote.  Now I am unable to find the U1 remote under the add bluetooth device.

 

I deleted the Fire TV from the app, and re-installed.  Still no luck, it still will not show up on the fire stick. I have reset the U1 to factory settings, and re-installed the fire stick, and still can not find it in the fire TV add bluetooth device setting. How do I get the FireStick to re-recognize the U1 remote so I can use the buttons on the U1 to control the Firestick.  Also, when I re-install the Fire TV from the U1, it closes the app every time (I have re-installed the fire TV many times).  When I restart the app, is shows the fire TV was added, but I can not still find U1 under the fire TV find blue tooth device.

Please help.