How to whitelist digitalocean load balancer in kubernetes network policy?

I’ve configured next network policy in my namespace:

kind: NetworkPolicy
apiVersion: networking.k8s.io/v1
metadata:
  name: np-testing-allow
  namespace: testing
spec:
  podSelector: {}
  ingress:
  - from:
    - namespaceSelector:
        matchLabels:
          purpose: monitoring
    - namespaceSelector:
        matchLabels:
          purpose: ci
    - namespaceSelector:
        matchLabels:
          environmentName: testing

But after that managed load balancer for nginx-ingress is down. How I can whitelist managed load balancer in network policy?

I’ve already tried to whitelist VPC CIDR and load balancer public IP and it didn’t help