Unauthorized Nebula Charge On PayPal

I am writing regarding two unauthorized charges of 49.99 USD each that have been taken from my bank account in connection with Nebula, even though I do not have any active subscriptions on my Google account or Google Play. Both payments were taken from my Visa debit card, and in my bank transaction details, the merchant appears as PayPal. The first charge occurred about three months ago, around the beginning of the month, and the second one was taken on April 11. I only noticed these payments later and confirmed that I have no corresponding subscriptions or purchases in my Google or Google Play accounts. I do have a PayPal account linked to this Visa debit card, but I have not knowingly authorized any recurring payment or subscription for Nebula for 49.99 USD. I tried repeatedly in the past to resolve and get a refund for the first 49.99 USD charge, but was not successful. Because of this experience, I am at least requesting a full refund for the most recent 49.99 USD charge on April 11 and the cancellation of any subscription or recurring payment that may be linked to my card or PayPal account without my clear consent. I kindly ask that my account and payment records be checked, that the latest 49.99 USD charge be refunded, and that any unauthorized or hidden recurring payments be stopped so that this does not happen again.