Smooth Scroll speed and easing configuration

I have the following problem
I have a page.php which includes a top menu.php
Each item of the included menu corresponds to a link to a Smooth Scroll instruction on the page.
Each Smooth Scroll anchor at the top of the relevant section
Everything works, but I would like to use the Smooth Scroll properties.
Unfortunately, however, I try to vary Speed and Easing and I don’t get any results. The scroll is always the same with any setting
Maybe someone knows why?