It looks like the service you are calling has accepted the data, and returned a 201 Created HTTP responses code and an empty list as the return value. Is this not what you are expecting to see? It could be the bug is actually on the service you are calling if it is not behaving to specification.
Thank you for the response.
If I call the PST method from Swagger then it works as expected and data gets inserted.
But if I try to call the POST method from microflow then I can see the success code but data is not inserted.