How do I prevent the cloud sync from overwriting the QGIS file?

[Figgy03]

Hi QField community.
I am a new user of QField and have some questions about the behavior of the QField sync. I configured the sync for a QGIS file. I have since added shapefiles to the QGIS file. When I complete Synchronize Current Cloud Project, the QGIS file is overwritten by the cloud file: it removes the layers that were added (and adds layers that were removed). How do I prevent this from happening? How do I make changes to the QGIS file and push all/some of these changes up to the cloud file? I don’t see an interface for doing this. I feel like I'm missing steps in the intended workflow.

Thanks very much for your guidance and help.