How to troubleshoot Azure blob upload using COT?

Hi Team,

Thank you for your attention. I followed, DB record created, but i can't seem to upload anything to azure storage. Could you point me to which line of code that I can look into for errors? No errors found so far.

Configuration in azure:
Azure Container Public Access Level: Container
Storage Account: backup
Container: dev

COT (version:
Virtual Field: Attachement Bytes[]
Value is retrieved on demand [checked]
Source Fields: AttachmentFileName
On Demand Handler: AttachmentBlobHandler
On Demand Style: Thumbnail

Blob Adapter configuration:-
Field: Attachment
Storage-System: Azure
Account: backup
Container: dev
Key: YK5Sd4rujRBQaBVzsTE.. etc from Azure
Path-Template: Attachment/{AttachmentFileName}

Database field:
AttachmentFileName NVARCHAR(255)
AttachmentLength (Int32)
AttachmentContentType NVARCHAR(50)
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