The exception I am getting is
org.glassfish.jersey.message.internal.HeaderValueException: Too many "Content-Type" header values: "[application/json, application/json]"
I was passing a request with content type = 'application/x-www-form-urlencoded' when I was getting this error. When I tried by not passing the content-type, I was still getting the same exception.
Please use the latest Karate version and you should be able to solve this problem: https://github.com/intuit/karate