csi-unity nfs claim pending

Hello all

I'm trying to configure csi-unity with nfs only provisioning. I've successfully installed the csi plugin with these params

#cat myvalues.yaml 

csiDebug: "true"
volumeNamePrefix : csivol
snapNamePrefix: csi-snap
imagePullPolicy: Always
certSecretCount: 1
syncNodeInfoInterval: 5
controllerCount: 2
createStorageClassesWithTopology: true
storageClassProtocols:
- protocol: "NFS"
storageArrayList:
- name: "CKM00XXXXXX50"
isDefaultArray: "true"
tieringPolicy: "2"
storageClass:
storagePool: Pool0
reclaimPolicy: Delete
allowVolumeExpansion: true
protocol: "NFS"
hostIoSize: "8192"
nasServer: "nas_14"
snapshotClass:
retentionDuration: "2:2:23:45"

when I try to claim a pv, it goes in pending state with the following error:

 failed to provision volume with StorageClass "unity-nfs": error generating accessibility requirements: no available topology found 

#k get sc
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
unity-nfs csi-unity.dellemc.com Delete Immediate true 14m
#k get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
myclaim Pending unity-nfs 13m

#cat claim-unity.yml
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: myclaim
spec:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 5Gi
storageClassName: unity-nfs

Any advice?

thanks

Matteo