How to specify ingress class

Traefik Traefik v2
1

I have two ingress controllers, haproxy and traefik in my cluster. I need to be able to specify the traefik ingress class on a ingress resource so that it uses the correct ingress controller / LB. Here is what I have so far

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: demo-tfk
  namespace: fvtt
  labels:
    ingress: demo
    version: 1.0.0
  annotations:
    kubernetes.io/ingress.class: traefik
    traefik.ingress.kubernetes.io/router.entrypoints: websecure
    traefik.ingress.kubernetes.io/router.priority: '20'
    traefik.ingress.kubernetes.io/router.tls: 'true'
    traefik.ingress.kubernetes.io/router.tls.domains.0.main:college.net
    traefik.ingress.kubernetes.io/router.tls.domains.0.sans: demo.college.net
  loadBalancer: {}
spec:
  tls:
    - secretName: college.net-tls
  rules:
    - host: demo.college.net
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: demo
                port:
                  number: 80

As you can see no load Balancer has been assigned. Am I doing this right?