It's possible:
* The name is misspelled: Double-check the spelling.
* The author uses a different name: Perhaps they have a pen name or go by a different name in some publications.
* The author is not well-known: They may be a self-published author or have only written in niche genres.
If you can provide more details about their work (genre, approximate time of publication, any other known information), it might help in identifying the author.