Can't remove stain at the back of new iPhone 13

Hello everyone!

I recently bought the iPhone 13 (midnight) a couple of days ago, and there's a stain on the back of the phone - stain stretches from the top right to the Apple logo. I've tried rubbing alcohol and a microfiber cloth to remove the stain, but that didn't work. Does anyone have any alternatives for removing the stain, or should I bring the phone to the Apple store and try to exchange it for a new one? Thank you!