GKE Ingress Using Internal IP

I have a GKE service app using golang. I want to make the app only accessible with same vpc (because it will exposed using kong to public domain). But everytime i make the internal alb ingress inside GKE, it returns an error like this

Error syncing to GCP: error running load balancer syncing routine: loadbalancer ad8b7iw3-gke-app-event-ingress-n1p8mv91 does not exist: googleapi: Error 400: Invalid value for field 'resource.target': 'https://www.googleapis.com/compute/v1/projects/gke-project/regions/asia-southeast2/targetHttpProxies/k8s2-tp-ad8b7iw3-gke-app-event-ingress-n1p8mv91'. An active proxy-only subnetwork is required in the same region and VPC as the forwarding rule. 

EDITED
For now the error return like this

Missing one or more resources. If resource creation takes longer than expected, you might have an invalid configuration. 

i have make svc and ingress yaml file to handle this:

ingress.yaml

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  labels:
    app: gke-app
  name: event-ingress
  namespace: gke-app
spec:
  ingressClassName: "gce-internal"
  defaultBackend:
    service:
      name: gke-svc
      port:
        number: 8003
  rules:
    - host: event.staginggke.my.id
      http:
        paths:
          - path: "/"
            pathType: Prefix
            backend:
              service:
                name: gke-svc
                port:
                  number: 8003

svc.yaml

apiVersion: v1
kind: Service
metadata:
  name: gke-svc
  namespace: gke-app
  annotations:
    cloud.google.com/neg: '{"ingress": true}'
    networking.gke.io/load-balancer-type: "Internal"
  labels:
    app: gke-app
spec:
  sessionAffinity: ClientIP
  selector:
    app: gke-app
  ports:
    - port: 8003 # Port output
      targetPort: 8000 # Container port
      protocol: TCP
      name: http
      nodePort: 30473 # Node Port Static
  type: LoadBalancer
  loadBalancerIP: 10.184.0.12
  externalTrafficPolicy: Cluster

Thank you for helping!!!

You are missing a proxy-only subnet. You need to create one in the same VPC/Subnet your GKE cluster is on

https://cloud.google.com/load-balancing/docs/l7-internal/setting-up-l7-internal#configure-a-network