Hi @Kumar, Arun ,
Thank you for posting query in Microsoft Q&A Platform.
When you use postman, you are running it from your local and your local machine may be within the allowed network of API hence it works. When you use web activity in ADF or Synapse Pipeline, try to use the IR from the network which has access to the network of your API. I would suggest have selfhosted IR installed in your local or in the machine which has access to your API and use same in web activity.
Please check below link to know about selfhosted IR.
Setting up Self Hosted Integration runtime in Azure Data Factory
Hope this helps. Please let me know if any further queries.
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