NO TOKEN RETURNED error while facebook autorization

Hi, do you know by any chance what can be a reason of the following error while fb account authorization?

“Can’t get Page Token. NO TOKEN RETURNED. Are you sure that user you are trying to authorize is an admin of the page? This message means user was authorized as profile, but page refused to return authorization token. This usually happens when user has no rights to post to that page.”

https://wordpress.org/plugins/social-networks-auto-poster-facebook-twitter-g/