Soon to be ex-client, please expedite

I queried a charge on my credit card. Was spun the most amazing story about said charge, so I paid my account off in October - it now has a small credit balance. The November statement reflected another charge. So I emailed the guy I'd dealt with before on 15 November, didn't get a reply, so I sent an email to the main complaint email addy on the 15th and again yesterday. It seems the longer you've been a client, the lower the service drops - I been with them since the mid 90's. I now want to close my account and want to know how I go about doing this and not jump through a lot od hoops as I AM REALLY ANNOYED NOW.