blank space in present mode + responsive

I'm trying to make my design responsive, but I'm running into an issue. When I preview it in Responsive Present mode, there's a large blank space appearing between some of my frames. However, when I preview it in the normal Present mode (without responsiveness), everything looks exactly the same as it does on the canvas. I'm not sure what's causing the extra blank space in the responsive preview.

pls help!! thank you in advance!