Checking the invoice to see if everything I had payed for was supposed to be in the package.
I would sympathize, but I hate it when people write "payed" instead of "paid." I don't care if "payed" is now the commonly accepted spelling; I will hold this Glaive of Law against the Earth.
(The only problem I ever had with FFP was when they left the Darkstone Hydra model out of my Wave 1.5 Kickstarter shipment. But the replacement arrived so quickly, it was almost as if they shipped it before I sent the email telling them it was missing.)