I am unable to buy books from the bookself , nor the computer

My child sim was doing his homework at the Library. And I forgot to put his homework in his inventory before we went home. I went back to the library to find it put couldn't. I tried looking in his inventory and also the family inventory but cannot find it. Then I tried to buy another homework book from the bookshelf. And the option to order isn't even there anymore. Same with the computer.