isFatal
Flag to indicate that something has gone wrong with Device Sync in a way that is not recoverable and SyncSession will be SyncSession.State.INACTIVE until this error is resolved.
It is still possible to use the Realm locally after receiving an error where this flag is true. However, this must be done with caution as data written to the realm after this point risk getting lost as many errors of this category will result in a Client Reset once the client re-connects to the server.