In order to restore data using the graphSON snapshot, here are the steps to follow
Check the snapshots folder in the graphadmin pod running in your namespace:
kubectl exec -it $(kubectl get pods -lapp=aai-graphadmin -n onap --template '{{range .items}}{{.metadata.name}}{{"\n"}}{{end}}' | head -1) -n onap -- ls -ltr /opt/app/aai-graphadmin/logs/data/dataSnapshots/
You should see something like below
-rw-r--r-- 1 aaiadmin aaiadmin 1353242 Nov 14 21:45 dataSnapshot.graphSON.201811142145