Margot Template Double Verticle Scroll Bars

Site URL: https://www.plushphotography.com.sg

Hi, 
Need some help with the following
Only realise the issue of 2 scroll bars when I found it hard to scroll down. 
Wondering how to remove the extra scroll bar.
Issue seems to show on chrome browsers(Chrome/Brave) but looks ok on Safari.

I have tried using these codes at the custom css but it doesn't seem to do anything.

.overflow-wrapper {
   overflow: hidden
}

and also

.overflow-wrapper { height: 100vh; }