azure aks tag filter not working

[veldpworld]

we use aks cluster to shutdown the resource (aks, vm, mysql etc) in azure cloud. It was working fine and suddenly its stopped working to filter using the below policy based on tags.

Policy

 - name: aks-offhour
    resource: azure.aks
    filters:
      - type: offhour
        tag: scheduler
      - or:
          - type: value
            key: tags.ENV
            value: PROD
            op: not-equal
          - type: value
            key: tags.AutoShutdown
            value: "true"
            op: equal

we use the below tags format:

scheduler :  off=(M-S,8);tz=Asia/Dubai  

(custodian) myvel@DPW-HO-693:~/issue$ custodian/bin/c7n-org run -c infrasub.yaml -s testoutput -u testpolicy.yaml --debug -v
2024-07-21 00:30:30,809: c7n_org:DEBUG Running policy:aks-offhour account:Infra Lab region:global
2024-07-21 00:30:34,693: c7n_org:INFO Policy resource counts Counter({'aks-offhour-vel': 0})

I have tried using the value type to match regex that is working fine. But using offhour its not filter any matching with this policy. Can anyone help me with this policy to match this tags?