Moodle on AKS slow with Azure File and no file when using Azure blob

Hello everyone.

I have a moodle running on Azure Kubernetes Services using an external Postrges DB.

I am actually trying to switch default storage disk to an azure storage account.

I have tried with Azure File, things looks good but application is very slow. Pages takes too much time to appear than normal time. Tried to use premium file share to improve performance but it is same.

I now want to use a blob or block container following this ( https://learn.microsoft.com/en-us/azure/aks/azure-csi-blob-storage-provision?tabs=mount-nfs%2Csecret#statically-provision-a-volume )

Tried to deploy an empty new moodle but seems moodle do not know how to write in container of a storage account.

Have anybody tried to do this please.?
any hint and help will be appreciable