I am made Facebook App with Facebook Login Product to publish post to my own Page (where I am only one admin) With this app I request pages_manage_posts, pages_read_engagement and pages_show_list permissions.

Got user User Access Token (even Long-lived) and after that - Page access token.

But when I try to make a POST request through Graph API Explorer I got error with message: "(#200) If posting to a group, requires app being installed in the group, and either publish_to_groups permission with user token, or both pages_read_engagement and pages_manage_posts permission with page token; If posting to a page, requires both pages_read_engagement and pages_manage_posts as an admin with sufficient administrative permission" }

Again: I'm admin of my own Page, I got all permission described in error message. So what am I doing wrong?