I request a refund

Hello, I'm a Korean Android user using the Samsung Galaxy Tab. After using the free premium experience on the Acrobat app, my premium subscription was paid because I couldn't cancel my subscription before the end of the experience, and after confirming this, I immediately canceled my subscription and asked the Google Play Store customer center for a refund, but in this case, the customer center answers to leave a refund request as the developer's contact information and it doesn't work out well, so I'm asking for a refund here. I didn't need a premium and I was in trouble with my life because a large amount of money was unintentionally withdrawn from my account. I also contacted Kakao Pay, the payment method, but the answer was to contact the app developer and I didn't even get a refund guarantee. Please give me a refund