Hi @Sreeni.dwbi Greetings! Welcome to Microsoft Q&A forum. Thank you for posting this question here.
You can process the messages in Service bus dead-letter queue using .Net FormatDeadLetterPath
method. A sample implementation to achieve this has been described in the following post
In addition to this, there are different approaches specified in the post How to delete/clear active/dead-letter messages from Azure Service Bus Queue? on a similar ask. Couple of approaches suggest using Azure portal or an API call - Receive and Delete Message. The path to your dead-letter queue to invoke your API will be of the following format - <queue path>/$deadletterqueue
Hope this helps. Please let us know if you run into any issues implementing any of the proposed approaches.
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