Hello
@Akshaya R,
This is definitely a peculiar situation. The only other thing I can think of, without seeing the actual definition of the Web API service entry, is to use Fiddler or Wireshark to capture the HTTP Request/Response created from Postman and the same Request/Response created while using the Web API service and then compare the two to see if there is some obvious difference in the headers, layout of the request, etc.
Outside of that, my recommendation is to move forward with the HTTP VBO for this integration. You can also open a ticket with Blue Prism support as it appears you may have identified a bug in the Web API service feature.
Cheers,
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Eric Wilson
Director, Integrations and Enablement
Blue Prism Digital Exchange
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