How long does it take to receive my YouTube Premium refund from the App Store?

I accidentally purchased to my friends youtube account. I want it refund. It says I got my purchase refund, but actually none of my credit came back to my account. Only youtube premium was got away from me. What’s the problem? I bought it with apple credit. It already passed more than 48hrs since you said refund done.

[Edited by Moderator]