Xfinity xr15 remote will not pair with TCL Fire TV MODEL 75Q691F

I have been trying to pair my new TCL Fire tv with the xfinity xr15 remote. I van get voice controls, channel up/down and guide to work but can’t get volume and power to work. Have done a full reset to remote, actually got a new remote from xfinity and I can’t find a code that will work. Any help out there would be appreciated