Sometimes a Facebook page can get disconnected from Post Studio. In most cases, simply reconnecting your Facebook account to Post Studio would solve the problem.
How to reconnect my Facebook page
1) Go to the "Settings" page
2) Click on "Change Pages"
Reasons for disconnects
1) Connecting multiple stores to Post Studio the wrong way. To connect multiple stores to Post Studio correctly, please follow
https://help.poststudio.app/en/articles/5265261-connecting-multiple-stores-to-post-studio
2) Posting too many times to your pages. Please follow (our guide) to figure out the maximum number of times you should be posting. https://help.poststudio.app/en/articles/5265346-how-many-times-a-day-should-i-post
3) Three months after you've last connected your Facebook page, the page gets disconnected automatically by Facebook. Simply reconnecting your page would solve the issue.
If you have any questions, please reach out to our online support and our team would be happy to help!