I got the same issue i was using js to open custom link to open the app since we rely on messenger to send our link to users to claim something in the app it was working a month ago but not anymore i did everything even setup meta tags as mentioned in facebook docs but nothing seem to work i had made an arrow pointing to the right bottom of the screen to open the safari which will open the app like i want please if any one has a solution just let us know thank you !!