Background sheet prints black

My layout sheet appears normal (white) in Layout, but when I export an image, or print to PDF it appears black. Why is this?

Thanks!

Hey Diane, go to File > Document Setup > Paper and check “Print Paper Colour”, this should make it right, assuming you’ve set paper colour to white!

This has just happened to me for the first time after using Layout since 2012!
Simple fix was that I had one of my stacked viewports as a Hybrid instead of Vector.
The Scene in Sketchup is a Hidden Line style for my floor plan linework.
Could be a Layout 2025 thing, who knows??
Eithway, it would print fine, but as an export it was black.
Hope this helps.