First, do a hard reboot of your cable box: unplug it, wait 30 seconds, and plug it back in. When it finishes going through the rebooting cycle, push the "guide" key on your remote. You will see a list of options. Scroll down to the "full channel guide" and push "select", and you will have your full guide back. I know this because I just went through this process, under the direction of Jane, a Time Warner CSR. Thanks, Jane!
This seems to be a problem with the network in your area. In this situation, there is little to do unless you contact the offices and express your concern. However, you can opt to subscribe to their services or buy a receiver for a clearer view of the channels.