Qliksense Rest api call using Post Method

[Ram2]

I am trying to Create a New Rest API Data connection using POST Method. When i give the Api link and Request body and click on Test Connection Popup says: connection successful, when i click on create connection it says Bad Request(No thing Else).

I try to make the same call using Postman and it is successful and got data. 

Not sure of the error. Can some help me out here