receipt validation don't work in IOS

We use Unity’s receipt validation when a user buys any product.
It works fine on Android but iOS doesn’t.
Many users have cheated purchases with frequency every few seconds.
Is there any solution to prevent this?
Thank you

Hi @ACEPlay2018 ,
Can you share more information on the receipt validation implementation within your game as well as logs from an iOS and Google purchase?

Also, I assume you are referring to this.