I have a simple POST request that requires a json Content-Type header and a body like
{ oneNbr: \"2016004444\", twoCode: \"@@@\", threeNbr: \"STD PA
Try adding a * header Accept = 'application/json' header. The one difference between Karate and Postman is that Postman tries to be smart and auto-adds an Accept header - whereas Karate does not.
* header Accept = 'application/json'
Accept