OpenShift docker push 500 internal server error

I am running OpenShift 3.11 version and followed instructions from this documentation: https://docs.openshift.com/container-platform/3.11/install_config/registry/accessing_registry.html

However, whenever I run the below command, I see the error:

docker push 172.30.<num>.<num>:5000/project/image
received unexpected HTTP status: 500 Internal Server Error

I also checked the output of registry logs:

oc logs dc/docker-registry

It blurts out huge output but here is what caught my attention:

imagestreams.image.openshift.io <> is forbidden: User "system:serviceaccount:registry" cannot get imagestreams.image.openshift.io in the namespace "<>": no RBAC policy matched"

Therefore, I am confused why I am getting this permission issue. As per the documentation, it should have worked and there should not be any need for image stream and I should be able to push docker images directly into the registry. Does anyone have an idea what I am missing here?

Source: StackOverflow