I am using AKS version 1.14.8 with helm version 2.14.0 and tiller version v2.15.2. RBAC is disabled on the cluster.

Any hints on why this error is happening?

helm list --tiller-namespace dev1 --debug
 ✔  11288  17:06:25 [debug] Created tunnel using local port: '54671'

[debug] SERVER: "127.0.0.1:54671"

Error: an error on the server ("") has prevented the request from succeeding (get configmaps)

tiller rolebinding:

kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: tiller-binding
  namespace: dev1
subjects:
- kind: ServiceAccount
  name: tiller
  namespace: dev1
roleRef:
  kind: Role
  name: tiller-manager
  apiGroup: rbac.authorization.k8s.io

tiller roles:

---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: tiller-manager
  namespace: dev1
rules:
- apiGroups: [ "", "batch", "extensions", "apps", "rbac.authorization.k8s.io"]
  resources: ["*"]
  verbs: ["*"]

tiller service account:

---
kind: ServiceAccount
apiVersion: v1
metadata:
  name: tiller
  namespace: dev1