I Want a Refund for Unauthorized Shortmax Debit Card Charges

I am writing regarding unauthorized subscription charges made by Shortmax to my PNC debit card. I did not knowingly authorize any subscription with Shortmax, yet payments have been taken from my account, sometimes twice in the same week. These charges have been appearing for about three weeks. For example, on May 7, there were charges of 12.49 and 19.99, and on May 13, there were charges of 19.99, 19.99, and 18.49. I attempted to contact Shortmax regarding these transactions, but have not been able to find any clear way to cancel the subscription or request a refund. Despite my efforts, the charges are still appearing, and I have no control panel or visible option to manage or stop this supposed subscription. I request that any Shortmax subscription linked to my PNC debit card be immediately cancelled, that all unauthorized charges for this period be fully refunded, and that no further payments be taken from my account without my explicit consent.