UPS stolen my return parcel

I cancelled the order at the day I ordered it but it still shipped. Then I received it and put the return label on, then gave it to UPS pick up guy the next day.

Tracking shows it delivered on the day after. But Apple sent me an email that "We have completed our review with the carrier regarding your shipment and have determined that we are unable to provide a replacement or process a refund."

Called the costumer service a few times and get a result that "the box is empty, you won't be refund"

I didn't even open the sealed box and simply just put the return label on. (I took some pictures of the unsealed box with UPS label)

Shouldn't it be Apple who claim the refund from UPS? Most possible is someone from UPS has stolen it...

I went to the police station but officer said I can't claim a report as it's not stolen at my home.

UPS provides no info they keep saying "we have a special agreement with Apple, you can't file a claim, we only provide info to Apple"

Anyone who has similar experience? How do you eventually resolved this? let me know thanks, i believe I'm in a crisis now. It's unfair that I did everything properly but I take the result of stolen