Is retaining customers for over a decade something Comcast cares about?

Hi. We recently sold our two businesses we had an account with Comcast Business in which we called and asked to be disabled. We were sent a disconnection letter and one of the two stores was correctly disabled but the other one was not. I am being told that there were supposed to be two different disconnection letters (Comcast's internal paperwork) and since that didn't happen we are being charged for 30 days after I signed that additional paper. As a customer of Comcast Business for over a decade, this seems unfair and I am now reluctant to do business with Comcast Business again when I open my new business so I ask.....Does Comcast care about it's customers that have been loyal for over a decade? Because right now it feels like it does not!