.umap failed to save

I keep getting the following error, specially when the Project auto saves.

I only have 1 instance of UE4 Open, and I have tried making a new map, but it seems to have happened again.

The asset ‘/Game/GameName/Maps/TestMap’ (TestMap.umap) failed to save.

Cancel: Stop saving all assets and return to the editor.
Retry: Attempt to save the asset again.
Continue: Skip saving this asset only.

any updates on this? I’m getting the same