JSON api login failure

I am using POST method to login into my web application. I get 200 OK status but gets login error in preview.

Below is my url

https://host:port/appname/oslc/j_security_check?lean=1

Authorization has “No Authorization” selected
Http Header has Content Type “application/x-www-form-urlencoded”
Http Body has j_username and j_password parameter with x-www-form-urlencoded selected.

Any help is appreciated

The info in the body may be wrong since the call is OK