It seems like the issue you’re facing is related to the Vulnerability Assessment feature enabled on your SQL server or one of its underlying databases. The error message: "SqlVulnerabilityAssessmentStoragefullApiIsEnabled" happens when the version of the database or server is incompatible with the current Vulnerability Assessment configuration. This can sometimes lead to unexpected behavior, like the app service issues you’re experiencing.
Check Vulnerability Assessment Configuration, Go to your Azure portal. then proceed to the SQL server or the particular database. Under "Security," click on Microsoft Defender for SQL and view the Vulnerability Assessment settings. If the settings appear to be misconfigured or out of date, attempt to disable the Vulnerability Assessment and then re-enable it to reinitialise the configuration.
Verify that the SQL server and database versions are compatible with the latest Vulnerability Assessment feature. This error might occur at times if the storage account attached for Vulnerability Assessment is not configured correctly or lacks the appropriate permissions. Verify that the storage account for the assessment has proper permissions and is reachable.
Once you’ve adjusted the settings, restart your App Service to clear any lingering conflicts and see if the login issue resolves.
Enable vulnerability assessment on your Azure SQL databases express configuration
Azure SQL Database Versions and Compatibility.
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