Managed phone information
You probably have a Comcast profile in your iPhone if you use Comcast/Xfinity to access the internet.  You can remove the profile by following these steps:


Go to Settings --> General --> Profiles.
If you see a Configuration Profile named Comcast or Xfinity or something similar, tap it.
At the bottom you'll see a button named Delete Profile.  Tap, and confirm, to delete.
Restart the iPhone


Next time you try to access Comcast again, you'll be prompted to reinstall the profile.  There's nothing wrong with installing and deleting the profile, although it is annoying.  If you use the iPhone thru your company, like with Good Email, your company might've installed this profile.