I have a Facebook app that has been reviewed and approved. The app is also set to be live and available to the public (see combined screenshot below).
Screenshot of approval notice and app being public
However, when I try to integrate the "Send to Messenger" button on my website, it does not not show up consistently. By that, I mean that for some users (including some beyond the app admins/developers/testers), it shows up just fine. However, for other users, the button does not appear at all!
Based on the limited number of data points, I have, it seems that perhaps this is location-dependent? In particular, all of the users outside the US that I have asked do not see the "Send to Messenger" button.
Does anyone know why this might be the case? Here is the link to the page that should have the button: Webpage that should have a messenger button
