Hello,
First of all, please check if you have in your Facebook account a settings, a settings named ‘Link ownership’.
Also, you should enable in plugin’s ‘Main Settings’ -> ‘Enable Open Graph Meta Tags in Generated Pages’ checkbox. Also, this requires that you disable other plugins (or turn of their features) that generate OG tags for your page.
However, to make this fix work, you will have to introduce in the plugin, the page ID where you want to post, in the plugin’s ‘Main Settings’ -> ‘Facebook Page IDs (Link Ownership Verification)’ field.
How to get your page ID, using the official method:
Login to Facebook as an admin of your newsroom’s Facebook Page. At the top of the newsroom’s Facebook Page, click “Publishing Tools.” To the left, under “Posts,” click “Link Ownership.” Copy the id shown in the ‘content’ of the meta tag that is shown in the page and input it in the plugin -> ‘Main Settings’ -> ‘Facebook Page IDs (Link Ownership Verification)’ field.
More details in this article: https://web.socialnewsdesk.com/facebook/how-to-claim-link-ownership-on-facebook-a-publishers-guide/
If you don’t find this feature, you can follow the unofficial method: https://findmyfbid.com/ – input your page url and you will get it’s ID. Copy it and paste it in the plugin, to the ‘Facebook Page IDs (Link Ownership Verification)’ field.