Hi @zmsoft
Welcome to Microsoft Q&A Forum. Thanks for posting your query here!
In addition to above recommended solution from Amrinder Singh, we suggest you follow the below and give a try.
Storage doesn't provide any inbuilt mechanism to notify for SAS expiry as storage doesn't stores any SAS it's end. This is because SAS is confidential data and as part of compliance, need to be maintained on the customer side only. So, you need to maintain or track the expiry from your side only or setting up monitoring through logs and alerts is essential.
Additionally, you can track the token's expiration times manually or through automated scripts that check the expiration dates stored in your Key Vault. Which can be tracked through the scheduled tasks such as Azure Logic Apps, Azure Monitor Alerts.
Hope the above solution helps in addressing your query.
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