Requesting a Full Refund From MyIQ for Unauthorized Charges

I completed an IQ test through Myiq about a month ago from Nova Scotia, Canada. At that time, I agreed to pay a nominal one-time fee only to receive my IQ results, and I did not knowingly subscribe to any ongoing service or membership. Despite this, I have been charged 27 USD repeatedly on my Mastercard approximately every two weeks since then. So far, there have been three such charges of 27 USD, for a total of around 81 USD, and I consider these payments to be unauthorized because I only intended to make a single payment. I briefly mentioned this issue in a Myiq survey, but I have not yet contacted my bank, as I am first requesting that the company review and correct these charges. I request that all unauthorized recurring charges be cancelled immediately and that a full refund of the approximately 81 USD already charged be issued to my Mastercard. I also ask for written confirmation that no further payments will be taken from my card without my explicit consent.