My son bought a lot of games without permission, there were more than 7 thousand hryvnias, I wrote to ask for a refund, to which you replied (not refunded), can you return the money to the card he used to buy everything?

No one is in charge of me. I can't help you. We can't help you. As I said, we are other end users, not Apple employees. All we can do is make suggestions.

To prevent such future unauthorized purchases, follow the instructions on this page.

Prevent in-app purchases from the App Store - Apple Support

These forums are populated almost entirely by other users such as yourself. We cannot do anything about refunding the purchases.

While I can certainly understand the frustration of lost funds, it's a reminder for anyone to never hand an unlocked device to a child. They don't get the concept of real money.

All we can suggest is to plead your case to Apple again.