Advanced zoom share and recordings

I  used the advanced sharing option for PowerPoint where my slides are a backdrop. When I did a recording of the session, I was in a box at the top (with part of my slides) and NOT as I wanted - with me presenting and the slides as a backdrop.

How do I make a recording that does this - so I'm not in the little box but with the slide as a backdrop. I designed the presentation so that this would work - but it didn't. Please help - as otherwise the recording feature is flawed.