Can't Attach a Snapshot Policy to a File System
When creating or updating a file system and attaching a snapshot policy, an error occurs.
The snapshot policy is in an invalid state
You can't attach a snapshot policy that's in a DELETING, DELETED, or FAILED state.
Attach a snapshot policy to the file system that's ACTIVE or INACTIVE.
The file system is a replication target
A file system that's a replication target can't have snapshot policies attached.
Attach a snapshot policy to another file system, such as the source file system for the replication. Or, you could delete the replication so that the file system is no longer the target of a replication.