how to cancel a refund request

how do i cancel a purchase refund request from iTunes? I received an Apple Invoice email on 2nd Jan and thought that my kid has bought something without my knowledge. I went to ask for a refund. But after checking, the purchase is in Dec when was a legitimate purchase. So I want to cancel refund request urgently in case the items that I bought for my boy is being retracted. Please help.

Order no. MMG66YDMB7