Provided og:image is not big enough in Facebook linter

Question

I properly set og:image on my website, the facebook linter sees it (facebook debugger) however, it says the image should be at least 200x200, which it is not the case, my image is 250x250 image.

What could be causing the issue? Could this have anything to do with Cloudfront?

Edit: I got around it by switching from this image to another image which is a 
jpg image, but still I couldn't find the cause for the problem since the image
looks fine.

Answer 1

This was happening to me. I was only using the meta og:image tag. I added the following in the head

<link rel="image_src" type="image/jpeg" href="img_path" />

and it fixed the problem for me.

Answer 2

The thread here is pretty helpful: og:image Open Graph Warnings image size

Generally, FB's parser prefers images that are (1) measured in multiples of 100 and (2) square format.