I have just had a final demand from them and a threat to cut me off.
Problem - they haven't supplied me with anything for at least nine months and the reason for that was that they overbilled me by about £3000 and it took months to get it back. When I closed my account I was several hundred pounds in credit. I have not yet got that back either and now they are sending me threatening letters!
I want to hurt someone, I really do. Would that be unreasonable under the circumstances?