How to create a local custom role in OpenShift and apply it to a user within a namespace

Issue

• Need to create a local custom role and apply it to a user within a namespace

• After following Managing authorization policy creating a local role instructions for creating a local custom role while executing oadm policy add-role-to-user -n this error is shown:

oadm policy add-role-to-user <role-name> <user> -n <namespace>
Error from server: role "<role-name>" not found