I had a look at your account, but I do not see any history of purchases there. The domain you mentioned was never registered. Can you check if there could be a typo?
You’ll need to log in to the account that owns the subscriptions to cancel them. Here, on these public forums, we won’t be able to help you directly because we’d need some private information from you. That said, I’d suggest searching for the charge at https://wpchrg.wordpress.com/.
You’ll be able to use the Contact Us link on that page to contact our billing support team directly for further help with this.