Note: App developers are not eligible to issue a refund for you or on your behalf.
If the item you have purchased is not working as expected or can’t be used than some of the recent App Store and iTunes Store purchases might be eligible for a refund.
If your refund is eligible, your money will be refunded within 30 days by the Apple.
Please visit the address below for more information about refunds: https://support.apple.com/en-us/HT204084
If you can’t find an item in your purchase history, here is what you need to do. Keep in mind that you need to be signed in with the same Apple ID that you purchased the application from. Also, it is important to know that it’s not a purchase of one of your family member which is charged through your payment method.