Enable diagnostic logging and Access to Portal error logs !!

Please refer the docs link on Portal Diagnostic / Error Logging.

If you are unable to enable diagnostic logging due to “incorrect connection string”, please create a container called “telemetry-logs” in the storage account. This is a workaround option for a known issue.

Please note, at this point there is a provision to configure Azure Storage using connection string and there is no options to use SAS Key.

References: https://docs.microsoft.com/en-us/dynamics365/customer-engagement/portals/view-portal-error-log