Solid walls turning transparent during export

I’m having an issue with exporting as a 2D graphic pdf. The image which is displayed on sketchup appears different when exported - some of the solid walls and furniture become transparent. (The export is attached) I can’t figure out why - any help on fixing this issue would be great thanks!

This can happen if your model is too far from origin. Is it ?

Ahh yes it is. Will try bringing it closer thank you

Unfortunately that still didn’t solve the issue :confused:

Can you post the SKP?