I'm creating a plain vanilla AKS cluster with an ACR container registry and deploying a dummy service, something I've done a number of times before and should work but it's not - the service deploys without errors, I see the pod and the service are alive, the ports seem to match - but I fail to reach the app running in the pod.

Here is my YAML file:

apiVersion: v1
kind: Service
metadata:
  name: dummyapp-prep
spec:
  selector:
    app: dummyapp-prep
  ports:
    - protocol: TCP
      port: 80
  type: LoadBalancer
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: dummyapp-prep
spec:
  selector:
    matchLabels:
      run: dummyapp-prep
  replicas: 1
  template:
    metadata:
      labels:
        run: dummyapp-prep
    spec:
      containers:
      - name: dummyapp-prep
        image: dummyappregistry.azurecr.io/dummyappregistry.azurecr.io/dummyapp-prep:dummyapp-prep-18
        ports:
        - containerPort: 80
      imagePullSecrets:
      - name: secret

Everything deploys fine - I see the service and it gets an external IP:

kubectl get services
NAME            TYPE           CLUSTER-IP   EXTERNAL-IP     PORT(S)        AGE
dummyapp-prep   LoadBalancer   10.0.230.4   52.149.106.85   80:32708/TCP   4m24s
kubernetes      ClusterIP      10.0.0.1     <none>          443/TCP        26h

The pod is fine, I connect to it and curl the app on localhost:80. Still, browsing http://52.149.106.85:80 timeouts

I check the Azure Load Balancer - the IP is registered.

What else could be wrong?