Smush Pro images does not sincronize with CDN used by WPENGINE

Hello,

I have used Smush Pro to smush all my images in order to improve the speed of my site. But when I check again the load time, I see that there are some images not optimized. So when I see the images needed to be optimized (I have used Google PageSpeed and Hummingbird), I realized that I have images in the CDN that are not the same (the are not smushed) as in the wp folder.
Google Page Speed: https://developers.google.com/speed/pagespeed/insights/?url=https%3A%2F%2Fwww.dietistasnutricionistas.es%2F&tab=desktop

Example of image needed to be optimized: Al comprimir o modificar el tamaño de https://129jxg2yzb2b37j8xp4736zyhxr-wpengine.netdna-ssl.com/wp-content/uploads/2016/05/4070655695_dc78a07044_b_vegetarian-218x150.jpg puedes ahorrarte 5,6 KB (un 65 % menos).

Image already optimized: https://www.dietistasnutricionistas.es/wp-content/uploads/2016/05/4070655695_dc78a07044_b_vegetarian-218x150.jpg

I have tried several time to clear cache in WpEngine but I continue with the same problem. Any idea about what's happening here?

Thank you and best regards!