From time to time a pop-up window appears asking you to update access token because the access was expired. You can find details about this expiration here.
How can you refresh your tokens?
Step 1:
Go to your profile and find “Social Profiles" section.
Step 2:
Click on “Edit” icon.
Step 3:
Click on "Update Access Token". Do not forget that you have to be logged in to your page's social platform and you must have admin/editor roles on these pages.

Step 4:
Wait until you see "token updated" notication and save!
