Can not create new app

[r1jsheth]

I tried to run fn create app java-app but I am getting this error

Fn: Post http://localhost:9090/v2/apps: dial tcp 127.0.0.1:9090: connect: connection refused
See 'fn <command> --help' for more information. Client version: 0.5.91

I tried using sudo but not working.
I have checked there is no process working on 9090. (I tried for different ports)
I tried it on multiple machines - Ubuntu 16.04 and Ubuntu 18.04.
I was following tutorial provied on https://fnproject.io/tutorials/JavaFDKIntroduction/ thoroughly.