I actually had a similar thing happen with facebook, though we didnt share names.
We had full access. I could have signed this person up for the most expensive package, or even canceled their service.
Maybe that's how we drive their customer count and revenue down and put them out of business.
The first thing I said at the counter was "I know it's really hard to cancel Comcast, and I'm not going to accept anything but a cancel."
The girl at the counter smiled and said "We know ..." and immediately cancelled my account.
IIRC I logged out again and back in, same thing, my credentials worked. Went back to it a few days later and the password no longer worked
How have they not resolved this?