Prevent scrolling

Hi,

is there a way to prevent that the whole window is scrolling and not only the content of the Jquery Colorbox content.

I display a longer Form in the Jquery Colorbox and when I scroll down from a certain pint on the whole Page is scrolling down.

How can I prevent this behavior and set the layer fixed in the front.

https://www.ads-software.com/extend/plugins/jquery-colorbox/