Hello @Sirilakshmi Veerapaneni
You need to check the following things:
1) The SQL Client version you are using, are you querying from SQL Server Management Studio (SSMS), if yes then which version, I would suggest to use version 18 and above
2) Does your SQL User have correct permissions? You will need to provide access to schema of your external tables to the SQL User
3) If the SSMS version is correct, please check the value of your SAS token and try connecting it from Azure Storage Explorer to determine if the SAS is right and active
Do let me know of any queries