Pin It Button On Image Hover And Post problem

I have a blog (lanoisettegrise.com) on WP (the theme is Cocktail) and ’till few weeks ago I could save the images on my Pinterest boards from the articles with the Plugin ‘Pin It Button On Image Hover And Post’. Now if I repeat the action it says ‘Sorry! An error occurred in our system. Please try again.’ but for days now the situation has not stopped, making me lose many views. What could be the mistake? I tried other plugin but the results are the same, so I think it could be a WP problem. Can you help me?