Rectangle Fill Color Not Showing Up

Newish to InDesign and im working on a file that someone else put together at least a year ago. I need to change the background color of one page so I was trying to create a rectangle, fill it with a color, and then lock it in the background. But when I create the rectangle it's only showing up as transparent. I tried creating the rectangle on multiple pages and changing the color but it's still not changing. The only time the color shows up is if I use two fingers to zoom in and out but the second I take my hand off the mouse pad the color disappears again.