Featured image problem

Great plugin but I would like to see this resolved once and for all since I really want to keep in using this plugin.

Sharaholic doesnt show my featured image and chooses a replacement image. The Faceboog debug tool keeps on telling me that the image is to small but it isnt “Provided og:image is not big enough. Please use an image that’s at least 200×200 px.”

What could be the problem here?

I can provide an url but preferably not public

https://ww.wp.xz.cn/plugins/sexybookmarks/