While I haven't experienced this sort of thing very often in the US, whenever it does happen Amazon has either sent another package, refunded the cost of the order, and/or offered a free month of Prime. And it usually only takes 5-10 minutes in an online chat with customer service to figure out. There are definitely plenty of meh things about Amazon, but customer service is certainly not one of them.

YMMV, I'm not happy if paying for Prime and 50% of packages get lost, I call, and get them some days later than expected or get them later as expected and payed for next day delivery in the first time.