Prometheus Gateway problems

I’m trying to make a Istio Ingress Gateway for Prometheus and Grafana, and for some reason it doesn’t seem to work. I’ve done the same previously for k8s dashboard and Kiali and I had no problems.
This is my yaml:

apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: prometheus-gateway
  namespace: istio-system
spec:
  selector:
    istio: ingressgateway
  servers:
  - port:
      number: 80
      name: http-prometheus
      protocol: HTTP
    hosts:
    - "prometheus.lan"
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: prometheus-vs
  namespace: istio-system
spec:
  hosts:
  - "prometheus.lan"
  gateways:
  - prometheus-gateway
  http:
  - route:
    - destination:
        host: prometheus-k8s.monitoring
        port:
          number: 9090

Do you see anything wrong with this, or have a suggestion how to find the problem?

Nevermind. It was a DNS problem.