new Xr2 remote can't change channels

I just got a new xr2 remote and none of the codes that came in the manual worked. I looked online and found the code 10810. I used it and it only worked to program the power on/off, volume, mute and tv input buttons. I cannot change the channels or use any of the other buttons. I took back the remote to the comcast store and they gave me another xr2 remote with the same problem. I also tried resetting the cable box from my online account and it says that it wasn't able to reach the cable box to reboot it. I tried manually resetting the cable box by unplugging it from outlet and it didn't help. I don't know what to do.