Level cleared mesh variable

This is an issue that I’ve never encountered before. I’ve been working on this level for about 10-12 hours and I load it up today and the objects that I have placed in the scene are still there, but the static mesh variable that you can see in the details panel has been set to none. The default map to load for this project is the third person map and the same issues were present.

Please tell me that there is an easy way to fix this as this was going to be on my e-portfolio as my masterpiece.