Hello @Daya Sandhu ,
The issue is due to the naming conventions for a container in Azure Storage. Only "-" character is allowed and as the From and Date contains other characters due to which the error is occurring.
Do you wish to create a new "Container" for every attachment? If yes, you will need to perform string operation on "From" and "Attachment Last Modified Date Time" to get rid of the special characters which are not allowed.
Else as we will recommend you can create folders inside a container as shown below, so that you won't have to do any string operations.
In the screenshot
/test is the container.
Please let me know if there are any concerns. Thank you!