Check your recent bills for a note about changes in your channel lineup. In South-Central PA, my April bill for Digital Economy TV service (other tiers may be affected as well) included this:
Xfinity TV Changes Effective May 9, 2018: The Weather Channel will only be available on Expanded Basic, Family Tier and new Sports & News tier; Cartoon Network will only be available on Digital Preferred and new Kids & Family tier; Disney Channel will only be available on Expanded Basic, Family Tier and Kids & Family tier; TruTV will only be available on Expanded Basic; Food Network will only be available on Expanded Basic, Family Tier, and new Entertainment tier.
Comcast may have your lineup online at https://www.xfinity.com/learn/channel-lineup or https://www.xfinity.com/support/local-channel-lineup/. Service Centers and Xfinity Stores should have printed channel lineups. Check locations and hours at http://www.xfinity.com/support/service-center-locations/ to pick one up, or call Customer Service at 1-800-Comcast and have them send a lineup to you. Expect all of those to have gross errors.