I wanted to buy something on Amazon and needed three of them.
At the checkout I needed to adjust my quantity down because I was being restricted to just one item.
I have an Amazon Prime account so bought one item anyway. I tried to go through the buying process immediately to buy another and the site stopped me.
The next day I went back to Amazon and purchased a second item without any problem.
The day after that I tried to buy another but they were on to me. They wouldn't let me go through checkout. So I used another Amazon account.
This means that instead of paying for one delivery service, Amazon are paying for three deliveries. This makes no sense to me at all.