how do i report a fake business page on facebook?

[Kaz]

Copied from the Facebook help section:

How do I claim a Page that already exists for my business? Can I merge it with my business's official Page?

A Facebook Page may exist for your business even if you or someone else from your business didn't create it. This happens for a variety of reasons. For example, when someone checks into a place that doesn't already have a Page, a new Page gets created to represent the location.
If you've been removed as an admin of a Page that you want to manage, try contacting the current admins directly, if you know them.
If you're the official representative of an organization, business, celebrity, or band and someone else has created a Page for it, report the Page. If no one is managing the Page, you can request to claim it.