Comment 1 for bug 1868422

One possible item to check is if your tiller was initialized properly. From https://bugs.launchpad.net/starlingx/+bug/1856078 there is a known intermittent issue with tiller. The comments in that LP give instructions to see if this is the issue you are seeing and how to work around it:

If helm commands fail with the following error then a restart of the tiller pod will be required:
controller-0:~$ helm ls -a
Error: the server could not find the requested resource (get configmaps)
To restart the tiller pod use the following:
controller-0:~$ kubectl get pods --all-namespaces -o wide|grep tiller-deploy
kube-system tiller-deploy-d6b59fcb-g676l 1/1 Running 1 18h fd01:1::3 controller-0 <none> <none>

controller-0:~$ kubectl delete pods -n kube-system tiller-deploy-d6b59fcb-g676l

Confirm tiller was restarted:
controller-0:~$ kubectl get pods --all-namespaces -o wide|grep tiller-deploy

Please determine if the helm ls -a command works in your system or not and add a comment to communicate if your system has this helm issue.