[Omniusaspirer]

Unfortunately this is something that is intentionally designed to suck in almost all cases. It's even hard to pay someone else to do the canceling for you since you're generally required to offer up a lot of personal info to verify that it is in fact you that wants to cancel the account. I've personally had this range from phone number all the way up to SSN.

[paulgb]

I'm not a lawyer but could something like temporary power of attorney be used here?

[tombrossman]

Read your contract. It will almost certainly have a section on cancelling which will give a postal address. Write a short letter with your account details and whatever else the contract says to provide, and cancel by mail. It is faster than using the phone.

I've been doing this for years and it always works. Pay a tiny bit extra and get signed proof of delivery. This is helpful when the company 'accidentally' loses the cancellation. It's good enough to beat them in court and god help them if they ding your credit and you have proof you cancelled (and that they received your cancellation letter).