Assurant Damaged Device Returned - Not Recived

Husband put my damaged device in a drop-box at a post office and it has been lost from there. This was at the very beginning of Feb. 2021. We have been stuck with a $500 charge for the damaged device not being received. The tracking # they provided is no help and doesn't come up with anything at all with USPS. The person I spoke to on the phone for USPS said that the tracking number didn't come up with any information at all which was very odd for a prepaid label. She said that normally prepaid labels have some kind of either origin info or at least some info on where it is supposed to be shipped to. I called Assurant and they confirmed that it was the same tracking # they have on file for the damaged device they claim not to have received. They have said that the charges are valid since it isn't showing the device in their warehouse or in transit with USPS. USPS says there's nothing more I can do since I filed a missing mail request a month ago that hasn't turned anything up. When I straight up asked the Assurant rep "So I'm going to have to pay for a device that I no longer have because the post office lost it before it could be scanned" they just said yes. 

It feels like there's something really fishy going on with that. I also received the replacement device at the end of January, but it says that my claim was approved April the 2nd, which was 2 days before I filed the missing mail report. But they say that they still don't have the device. Weird that it would be approved a full two months after I had received the new device and sent the damaged one back. 

I will no longer be using any phone insurance so long as it’s through Assurant.