Wrong scroll position

Hi,

If my page is too short, then the scroll progress position won’t go to the end of the bar at the bottom of the page.
But when the page is long it works fine.

I am using a 100px top offset.

Here is an example on a page where it’s not working :
http://octaaave.com/dev/sollis/contact/

And a page where it’s working :
http://octaaave.com/dev/sollis/

Do you have any solution ?
Thanks in advance

https://wordpress.org/plugins/scroll-progress-bar/