Hintapp Continues Card Charge Attempts After Subscription Cancellation

I live in South Africa and some time in April I canceled a subscription I had with the website Hintapp.com / US. Despite this cancellation, the company has continued to attempt to charge my card, starting with an amount of R181 and then increasing the attempted amounts. All of these transactions have been declined by my bank, but the repeated attempts are worrying and unacceptable to me. I did not contact the bank or the company directly after canceling, because I expected the cancellation to be respected and the charges to stop automatically. However, the ongoing attempts show that my subscription and card information still appear to be active in their system. I request that Hintapp.com / US immediately and definitively cancel my subscription, stop all present and future charge attempts, remove and delete all of my banking and card details from their system, and provide me with clear written confirmation that my subscription is canceled and my payment information has been deleted.