No Comcast signal to one of my TVs. I've done all the troubleshooting and no help.

Hello--Today our main TV in the family room stopped showing any Xfinity/comcast content. The TV works and it shows streaming content through the apps accessed from the Samsung remote, but no xfinity channels, no guide, etc.. I am very tech savvy and have done all the troubleshooting myself and using your virtual assistant including rebooting the box for this TV, changing the remote batteries, being sure it is on the right HDMI source channel for Xfinity, checking connections, etc. The remote Xfinity XR11 remote does turn the TV on and off but does not show any Xfinity channels or affect the volume of the TV. I am going to stop by the Xfinity store tomorrow to exchange the remote, but I doubt that is the problem. If exchanging the remote doesn't fix this how do I get a technician to come out and fix this problem?