Amazon weirdness

The other week, I placed Gene Wolfe's Soldier of Sidon in the 'save for later' area of my Amazon shopping cart. This morning there was an 'important message' telling me that something I tried to place in my shopping cart didn't exist on the site; it took me a minute or two to figure out that it was the Wolfe that had gone missing. Later in the morning it was showing up as 'not available', but tonight it isn't even searchable.

Edit: curiouser and curiouser; it just happened again, this time to karentraviss's Matriarch,
but that is still available for pre-order, and I was able to put it back.