Twitter Timeline Widget is blank


I have a problem - it may be a bug.

I did the following:
-I created a widget here:
-then, I copied the HTML onto my site:

What is weird is the widget does not even show in the “Preview” area when I create a widget. I am tearing my hair out, because I cannot figure this out. I think it is a twitter issue because even in the “Preview” area when I create a widget it does not show.

Is it my account? Why is the widget not showing up? Anyone know why?