Facebook issue: The following required properties are missing: fb:app_id

I am having a problem with Facebook thinking my web site is spam. When I post links to my web site in my Facebook group, several people are getting sent to a spam web site. I ran the Facebook debugger tool and got this message:

The following required properties are missing: fb:app_id

I don’t understand what this means and if this is related to the issue with Facebook. Is there something I need to do in the plugin?

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