Cannot post to a Facebook page I manage (“Post As” blank)

Hi
I have the AddToAny Share plugin installed and have been using it on my sites for a few years. However recently I have been having an issue with not being able to share a post to some of the Facebook pages that I manage. When I click the Facebook share icon, the pop-up opens, I usually select the ‘Share on a Page you manage’ dropdown, choose the Page I want to share to and the ‘Post As’ field is automatically filled in (with the same page as I’m sharing to). See link to screenshot image here.

However, recently this isn’t happening: the ‘Posting as’ text is there but doesn’t autofill and there’s no way to edit it. Without the Posting As field completed, the post cannot be shared. See link to screenshot image here.

I manage 16 Facebook pages and about 10 are showing this same error.

Can you please advise?

Regards
Paul

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