I did the same library quest twice, buying the required item twice, and got an error and no reward. Twice. I'd cut and paste the screen, but it's a lot of text.

are you sure you clicked on the buy button for the item since it doesn't always automatically click properly

Yes. I bought it from the Book Nook and my offer was accepted. Twice.

was the book [item2=the ontra that could] ?

It was!

This has been reported on the board linked below. Feel free to post there. Thanks!

Extra Pet Space