Files Editor Charged Me After One-Time PDF Payment

I used the Files Editor service on 22 June for a one-time PDF editing payment and completed my transaction with the understanding that it was a single-use service. However, on 25 June, an additional amount of $49.95 was deducted from my bank account without my consent. On my bank statement this second transaction appears as “pdfsupport.com”. At no point did I knowingly agree to a recurring subscription or ongoing payments. I believed I was making a single payment only for PDF editing, and I was not clearly informed that any subscription would be started or that further amounts would be charged. Due to this, I request a full refund of the $49.95 that was deducted on 25 June, and I also ask for any related subscription or recurring payment associated with my details to be cancelled immediately. I would like written confirmation that the subscription has been cancelled and that no further unauthorized charges will be made to my account.