Bookmarks: problem when seeding DB

Started to do the Bookmarks proj. and when I reached the point when I had to seed the DB, this is what the console gave as feedback:
ActiveRecord::UnknownAttributeError: unknown attribute: book_id
Caused by:
NoMethodError: undefined method `book_id=’ for #Review:0x000000050a4a38
Did you mean? book=
So I am wondering what did I miss?
Any thoughts?
( I am pretty sure I did everything according the instructions. Even checked out the video walkthrough.
No progress.
Would love any help, thanks!