10 Minute English Charged Me After Free Trial and Won’t Refund

Hello, I downloaded the 10 Minute English app and used it during the advertised 7-day free trial period. I did not authorize any payment or approve a subscription. However, after the trial ended, the app automatically charged my credit card for a full 1-year subscription—without notifying me or asking for my consent. This was done completely in the background, without my approval. I am now requesting an immediate cancellation of the subscription and a full refund of the amount charged. I did not agree to this, and it is unacceptable to be billed like this without any warning. If this is not resolved quickly, I will be forced to take further action. Please assist me in resolving this issue as soon as possible.