Facebook not sharing individual posts

Hi, I’ve been running this website for about two years now and everything has worked fine. Last week for some reason Facebook decided it will only share the main domain and not individual posts… So now, every time someone clicks on the Share button below an individual post the actual website https://www.bilingvni-vychova.com/ gets picked up and posted to FB, rather than the post itself. The first time this happened was last week when I went to share one of my older posts, which until then had 253 likes, clicked the share button and instead of the post getting posted to FB, the main domain got posted. At the same time, the share number for that post went up from 253 to 903, which is the number of likes for the main domain, I suppose (since I changed my front page from a static page to a blog page last year there’s no longer a Share button for the root domain, or so I thought…). Now, every time someone clicks on the FB share button below any post, the number of likes for that post goes up from what it was to that ridiculous number so I now have several posts with 906 likes… I’m not aware of any changes I had made previous to this happening… I’ve tried deactivating all the plugins and switched to the WP default theme but nothing changed. I’ve tried using a different FB plugin but nothing changed. I would be grateful for any ideas. Thanks.