Ah this is crummy, sorry its happening! Just to clarify because it isn't noted in the OP, did you purchase insurance that covered the total value of the package when you shipped the item? You usually need to specifically ask for it "Hi yes I'd also like to insure this for $2200 etc" when you go to the post office to ship your package, and thats what's going to make all of the difference.

If so, don't bother with the phone, go straight to the post office! I've never had luck with them on the phone and they tend to be a lot more helpful in person.