When I upload a screen to view it as a mobile prototype, I'm not getting a scroll bar. So I can't scroll down the design. When I first signed up it worked but now it doesn't. See file attached. No scroll bar on the right. I can't scroll up and down.
What am I doing wrong? It's a 320 pixel width jpg. Not even 1Mb in size.
Even screen I had previously uploaded and had worked don't work now.