I am trying to learn the basics about istio so I have gone through the official documentation here in order to create a 80/20 canary deployment, I have also follow this guide from digitalocean which explains it very easy for a simple deployment https://www.digitalocean.com/community/tutorials/how-to-do-canary-deployments-with-istio-and-kubernetes.

I have created a simple app with 2 different messages on the homepage, and then created the virtualService, Gateway and the destination rules. I (as mentioned in the guide) get the external ip with kubectl -n istio-system get svc and the try to navigate to that address but I get a 503 error. It seems very simple but I have to be missing something. These are my 3 files (as far as I understand there are no more necessary files):

apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  namespace: istio
  name: flask-gateway
spec:
  selector:
    istio: ingressgateway
  servers:
  - hosts:
    - "*"
    port:
      name: http
      number: 80
      protocol: HTTP
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: flask-app
  namespace: istio
spec:
  hosts:
  - "*"
  gateways:
  - flask-gateway
  http:
  - route:
    - destination:
        host: flask-app
        subset: v1
      weight: 80
    - destination:
        host: flask-app
        subset: v2
      weight: 20
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
  name: flask-app
  namespace: istio
spec:
  host: flask-app
  subsets:
  - name: v1
    labels:
      version: v1
  - name: v2
    labels:
      version: v2

Here are the yaml with deployment and services for v1 and v2:

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    version: v1
  name: flask-deployment-v1
  namespace: istio
spec:
  replicas: 1
  selector:
    matchLabels:
      app: flask-app
  template:
    metadata:
      labels:
        version: v1
        app: flask-app
    spec:
      containers:
      - name: flask-app
        image: latalavera/flask-app:1.3
        ports:
          - containerPort: 5000
        resources:
          requests:
            cpu: 100m
            memory: 128Mi
          limits:
            cpu: 250m
            memory: 256Mi

---
apiVersion: v1
kind: Service
metadata:
  name: flask-service
  namespace: istio
spec:
  selector:
    app: flask-app
  ports:
  - port: 5000
    protocol: TCP
    targetPort: 5000
  type: ClusterIP

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    version: v2
  name: flask-deployment-v2
  namespace: istio
spec:
  replicas: 1
  selector:
    matchLabels:
      app: flask-app
  template:
    metadata:
      labels:
        app: flask-app
        version: v2
    spec:
      containers:
      - name: flask-app
        image: latalavera/flask-app:2.0
        ports:
          - containerPort: 5000
        resources:
          requests:
            cpu: 100m
            memory: 128Mi
          limits:
            cpu: 250m
            memory: 256Mi

---
apiVersion: v1
kind: Service
metadata:
  name: flask-service2
  namespace: istio
spec:
  selector:
    app: flask-app
  ports:
  - port: 5000
    protocol: TCP
    targetPort: 5000
  type: ClusterIP

I have added the labels version: v1and version: v2to my deployments, and I have also used the kubectl label ns istio istio-injection=enabled command, but they are not working anyways