popup screen on iphone is not scrollable

My popup on my iphone is scrolling the screen behind the popup instead of the data within the popup.  
https://drive.google.com/file/d/1CnrjWgjbOP6oEJNd6yENZEW5VyR9Xi8V/view

It is an iframe that is in a template.  On the desktop I see a slider on the right side.  On the iphone I do not see a slider.  It will slide up and down (sometimes) if I get right on the right side of the popup.

Do you see the problem in safari and chrome on browser? The iFrame could be causing all sorts of problems. What browser are you using and have you tried the others?

Yes.  It seems its is worst when there is a popup on a popup.