If you are still having issues, try rebooting the RokuTV immediately after it fails to pair. (Settings/System/Power/System Restart).
Hopefully, after the reboot, you will be able to complete the pairing process successfully.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102