Consistent URL

Hello,

I am trying to speed-up my wordpress site with GTmetrix.

Gtmetrix tells me to Serve these two resources from a consistent URL

http://askaparis.com/wp-content/themes/child-mystile/style.css
http://askaparis.com/wp-content/themes/child-mystile/style.css?ver=4.6.1

The problem is that the file style.css?ver=4.6.1 doesn’t exist. I only have one style.css in the folder /chils-mystile.

If I do not activate my child theme and use original Mystile theme, this problem dose not appear.

Any help would be great.

Best regards.

Coq Vi.