This is not the only book that's got the wrong cover. It's something that has been reported before, and IIRC BookLikes have even promised to give users the option to correct cover images at some point in the future (whenever they get around to giving users what would be the equivalent of "librarian" powers on Goodreads). Can't do any harm to flag it again, though; if you want to do so, the best way is to either post it on the
Bug Reports thread, or on
Feature Requests. Both of these threads are monitored regularly by the BookLikes team.