Widgets Won't Drag

I’ve just installed a new blog, https://www.abcwritersnetwork.co.uk so far it has only the default theme, I’ve added in a few posts, I’ve went over to the Widgets area and noted that the widgets won’t drag.

In the centre of the widget page there are all the widgets ou’d expect, on the right hand side there are Primary and Secondary Widget containers each containing widgets but none of them are clickable.

Any suggestions as to what is going on.

Kevin