"The 'computer' is lying" situation is a problem generally. I didn't receive a 16-port switch and another small item a few years back even though it was noted as delivered. Neither Amazon nor UPS would do anything about it. A couple weeks later (I think it had been snowing) I discovered the package tossed in a ditch to the side of my driveway. Everything was actually fine but I had reordered and didn't have a need for a second switch.

I've had a similar situation, where the delivery guy said I wasn't home, so he left the package at some drop-off point. It was a small package and the house has a big ass mailbox. There wasn't a drop-off notice, either. And both my parents and I were at home, with my mom hanging around in the garden in plain view of the mailbox.

The opening hours of the place were a PITA, so after two attempts I called up Amazon and complained about this. Sure enough, they sent the package again without trying anything funny.