I recently had this problem so when I figured out how to solve it, I decided to share it here in case if anyone else is having the same problem because I noticed that the problem is not uncommon.

You may have noticed that if you want to share a like on facebook, it will pull up the title of the post, a litle description and an image from the post you want to share like the one in the image below. But sometimes it will show just the URL of the homepage of the website in the preview or showe the wrong title and description. This isn't normal. This can be caused by a lot of different probs that I can't go into the details here. I'm here to offer the solution to that.

To solve that simply head over https://developers.facebook.com/tools/debug/ , copy and past the link you want to share into the URL box and click debug then click on "fetch new scrap information". If the new page returns 200 response code, then you know your problem is solved.
If it didn't return 200 response code, then your case is critical. You can share the error massage return here let's see how we can fix it.

hmm