Shortmax Innovations Continued Charging Me After Subscription Cancellation

On 8 April, I cancelled my subscription with Shortmax Innovations for the Corona UAA service. Despite this cancellation, I was still charged on 15 April, 22 April, and 29 April. When I contacted customer service, they told me they needed my email address and information, which I have already provided to them. However, the charges have continued, and the situation has not been resolved. I request that Shortmax Innovations immediately stop all further charges related to this cancelled subscription and refund the amounts that were charged after 8 April. I also expect a clear written confirmation that my subscription is fully cancelled and that no further payments will be taken.