Exterior Wall Material Change Returns to Default

[Jimbtv]

I am working on a personal design/build of a barndominium. In some instances, when I change an exterior wall's material from lap siding to ribbed sheet metal, some of the walls revert back to lap siding. This can occur when I reload a saved drawing and sometimes when I change a wall material somewhere else in the building. Most walls retain the change but some don't.

 

Any ideas?

 

I am working in Home Designer Suite 2023