* The name is misspelled. Perhaps you meant a different name, like Michael Mann, Michael Caine, or Michael Keaton?
* The individual works under a different name. Perhaps they have a stage name or use a pseudonym.
* They are a relatively unknown actor or filmmaker. Many talented individuals work in the industry without achieving widespread fame.
If you could provide any more information, such as a specific project they might have been involved in, or a general description of their work, I might be able to help you find the right person.