I'm trying to deploy MongoDB on Google Cloud using Kubernetes. However, I'm having some difficulties. It says:

error converting YAML to JSON: yaml: line 29: found character that cannot start any token

However, on line 29 there's only a space indenting the line, as shown below.

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mongo-pv-claim
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 20Gi
---
apiVersion: v1
kind: Service
metadata:
  name: mongo
  labels:
    name: mongo
spec:
  ports:
  - port: 27017
    targetPort: 27017
  clusterIP: None
  selector:
    role: mongo
---
apiVersion: apps/v1beta1
kind: StatefulSet
metadata:
  name: mongo
spec:
  serviceName: "mongo"
  replicas: 1
  template:
    metadata:
      labels:
        role: mongo
        environment: test
    spec:
      terminationGracePeriodSeconds: 10
      containers:
        - name: mongo
          image: mongo
          command:
            - mongod
            - "--replSet"
            - rs0
            - "--smallfiles"
            - "--noprealloc"
          ports:
            - containerPort: 27017
          volumeMounts:
            - name: mongo-persistent-storage
              mountPath: /data/db
          volumes:
            - name: mongo-persistent-storage
            persistentVolumeClaim:
              claimName: mongo-pv-claim

Could somebody point me to where I'm doing something wrong, or more resources on the matter? I've only recently started using Kubernetes, so would appreciate any information.