Remote quit working

I have the Cox Mini IR URC2220 remote and recently the on/off, along volume controls have ceased to work. I attempted to reprogram to the remote to the box and to the TV, use the cox support page, but was unsuccessful. After contacting the Cox representative, a new remote was sent to me and reprogramming was reattempted and again without change. Additionally, I change HDMI inputs and unplugged the Cox box, although not a full two minutes, which I just recently read and still the problem persist. Any help in this matter would be appreciated. Thank you