I need object comment list with their authors for extraction statistical information about author and their comments. FB Graph api allow me to get comment list but there no way to get information about comment author.
Since v2.11 of the Graph API, you can only get user information about comment authors by using a Page Token. You can only get a Page Token if you manage the Page. There is no way to get the author data if you do not manage the Page.
Changelog: https://developers.facebook.com/docs/graph-api/changelog/version2.11#gapi-90
Also, make sure you ask for the relevant fields: /post-id/comments?fields=message,from