I've had problems being charged twice for 6 months of sports passes and it appears it's because I have two accounts registered to my name and payment details (albeit with separate accounts and email addresses).
After some effort I've had the double payments refunded, however I now want to delete this account and all my details associated with it to avoid similar problems, and to ensure the data isn't sitting there.
If you select your profile icon, you should then see an option for 'My Settings'. Select that and under the 'Personal' heading you will have a drop-down box. Select that and you should see the option to 'Close Account'.