Why am I not eligible for a refund on Instagram from the App Store?

I recently purchased Instagram verification on October 4th. I canceled the subscription through the App Store and requested a refund on your website. However, I mistakenly renewed the purchase through the App Store. After one day, the website indicated that my refund had been processed, but I did not receive it. When I checked the App Store, I noticed the renewal and canceled it again. I attempted to request a refund once more, but the website now states, "You have no purchases that are eligible for a refund." Could you please assist me in resolving this issue and processing my refund? I would greatly appreciate your help.

[Re-Titled by Moderator]