[AreFeetShoes]

Another user had this experience fairly recently:

https://sinister.li/Thread-GAME-co-uk-no...light=game


They claimed a DNA on the physical item which worked but I believe there was no tracking, and it was the digital code which caused the issue. I'd say give it a try and report back to us, I believe Royal Mail tracking requires a signature from an occupant and under no circumstances will they leave an item outside though