How frustating. I hope it is found soon.
This reminds me of when I ordered something from a craft catalog years ago (before the internet and easier parcel tracking). It was shipped UPS, but never arrived at my house. I called the local UPS office and was told it was left at the door of the porch on the side of the house. Well, my house did not have a side porch, but my neighbor's did. I did not know the neighbors (we were fairly new to the neighborhood), but went to their house and asked. They said: "Oh yeah, we got this package for you the other day. It's sitting here on the kitchen counter"! Argh...
Maybe it's worth checking with the neighbors....