Maybe it’s saying you shouldn’t travel to the US.

Go to the consulate tell them your passport is lost in the mail, it is their job to get you a new one.

I work in post, but not in Canada.

Postal facilities often move >100k items a day. Or much more. Occasionally, a parcel will go missing, lose its label, be destroyed and unrecognizable, or end up in a place no one thought it was possible for something to fit. Thin items are especially bad for this.

There is only so much that can be done to try and follow it via CCTV and/or scans. Whether they have done everything practical, I don't know.

We don't machine sort passports (which reduces the chances of it getting lost/destroyed), but I think that's only new passports coming from the printers. Your passport may have been treated like any other courier item - assuming Canada's processes are similar.

The rest of it is probably a question for a travel sub.

Have you tried calling the last place it was at? And it never hurts to let your fear, panic, sadness show. You need an inside person to try to track it down

Wow this freaking sucks. I'm sorry.