Go to your Facebook app
On the left sidebar, Click Settings
On the main side, click "Add platform"

Select "Website"
On the "Site URL" enter your site's URL.
Click "Save changes" button.

On the left sidebar, Click Settings
On the main side, click "Add platform"

Select "Website"
On the "Site URL" enter your site's URL.
Click "Save changes" button.

Updated on: 07 / 21 / 2021