is using an image from Facebook copyright?

[Jay]

Yes.

If you were not the owner of that image then you have no legal rights to use it with the permission of the owner. That involves either their straight forward permission i.e. "go ahead" or if you pay a fee.

There are some exceptions - you might claim "fair use" if your intent was to use it in a news report, educationally etc.

If that's not the case then you are in the wrong and will need to take the image down and possibly agree some compensation.