PicsArt Charged ₺520 After I Canceled My Free Trial and Did Not Send a Reminder

I started the 7-day free trial of the application called "PicsArt" and it said that a reminder message would be sent on the last day and that if the subscription was not canceled, an annual subscription would be started. On the sixth day, I did not receive any message or email, but since I was not satisfied with the trial period, I went and canceled my subscription. The next day, ₺520 was withdrawn from my card without my knowledge and I received a message that my annual subscription had started despite my cancellation. This is not acceptable. I do not want a subscription, I was not satisfied with the application during the trial period and I will not use it. I demand my money back, otherwise I will have to initiate legal proceedings.