HBO NOT NEEDED

Credit applied FAST

I used to work for Comcast...

I'd suggest calling and speaking with someone directly. There's
something about the give-and-take of a phone call that gets more
accomplished than text-based correspondence could ever do.

If you actually spoke with someone regarding this, there should be
records on your account. Whoever you speak with should be able to see
when it was that you called about this and should be able to rectify
it. They may be able to figure out what went wrong as well. Though
there's no guarantee of that.

When you call, keep in mind that the person that you speak to is not
the one that caused the error. If you are really pleasant on the
phone, and ask nicely, they will likely take off all of the
over-charge, assuming there is documentation that you spoke with
Comcast about this before.

Since you paid that $60 for HBO, which you could view, I don't think
you're entitled to a refund. Do you have copies of your emails? If
so, this may help in proving the case that you did, indeed, contact
them to discontinue HBO. Did you make a note of to whom you spoke
when you told them you no longer wanted that channel? Whenever I talk
to a company to make a change in service or have a dispute on billing,
I always make a note of the exact time, date, and with whom I spoke.
Don't know in what area you live, but here in my locality we had
trouble with Comcast when they started up, but now I couldn't ask for
better service.