Why did my backup job fail with 'snapshots-bad-state' event type?

You receive an event notification with the event type 'snapshots-bad-state'.

The backup job failed to delete a snapshot that has passed its retention period because the snapshot was not in a stable state.

Check the snapshot to see when it reaches 'stable' or 'failed' status. Then, either wait for next backup job to delete the snapshot or delete the snapshot manually.