For years now, Facebook has prevented people from posting links to Counter Social.
Although if you're just trying to link to here the link itself may be the problem.
It's counter(dot)social without the index html stuff.
If you're trying to link a post someone made here, unless they've got PLP enabled I'm not sure it'd work. Pretty sure without the Public Landing Page enabled, people's posts are private and will only show here. It'll be a dead link otherwise.
In general, FB will not allow CoSo to be linked in either messenger or on someone's page.
The reason for that is they don't want people leaving FB because they can't data mine them if they leave for somewhere better.
@Hisabah probably being blocked by FB lol