Rabbitmq deployed on GKE can connect to UI management but cannot connect to 5672

Question

I have setup rabbitmq on GKE using the applications. Everything is setup according to the tutorial guide and at the end I can access the UI management on the IP 35.203.xxx.xxx:15672 (Loadbalancer public IP). when I try to connect to amqp on 5672 it gives error Unhandled exception. RabbitMQ.Client.Exceptions.BrokerUnreachableException: None of the specified endpoints were reachable

My c# code is

ConnectionFactory factory = new ConnectionFactory();
factory.Uri = new Uri("amqp://username:[email protected]:5672/");
using(var connection = factory.CreateConnection())
using(var channel = connection.CreateModel())
{
    ...
}

the code that I'm running is on my local computer. I have created new user for rabbitmq and added all the ports in GCP firewall as well.

Any help is appreciated.

[Updated] My deployment yaml

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: rabbitmq
spec:
  serviceName: rabbitmq
  replicas: 4
  selector:
    matchLabels:
      app: rabbitmq
  template:
    metadata:
      labels:
        app: rabbitmq
    spec:
      serviceAccountName: rabbitmq
      initContainers:
      - name: config
        image: busybox
        command: ['/bin/sh', '-c', 'cp /tmp/config/rabbitmq.conf /config/rabbitmq.conf && ls -l /config/ && cp /tmp/config/enabled_plugins /etc/rabbitmq/enabled_plugins']
        volumeMounts:
        - name: config
          mountPath: /tmp/config/
          readOnly: false
        - name: config-file
          mountPath: /config/
        - name: plugins-file
          mountPath: /etc/rabbitmq/
      containers:
      - name: rabbitmq
        image: rabbitmq:3.9-management
        ports:
        - containerPort: 4369
          name: discovery
        - containerPort: 5672
          name: amqp
        - containerPort: 15672
          name: management
        env:
        - name: RABBIT_POD_NAME
          valueFrom:
            fieldRef:
              apiVersion: v1
              fieldPath: metadata.name
        - name: RABBIT_POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        - name: RABBITMQ_NODENAME
          value: rabbit@$(RABBIT_POD_NAME).rabbitmq.$(RABBIT_POD_NAMESPACE).svc.cluster.local
        - name: RABBITMQ_USE_LONGNAME 
          value: "true"
        - name: RABBITMQ_CONFIG_FILE
          value: "/config/rabbitmq"
        - name: RABBITMQ_ERLANG_COOKIE
          valueFrom:
            secretKeyRef:
              name: rabbit-secret
              key: RABBITMQ_ERLANG_COOKIE
        - name: K8S_HOSTNAME_SUFFIX
          value: .rabbitmq.$(RABBIT_POD_NAMESPACE).svc.cluster.local
        volumeMounts:
        - name: data
          mountPath: /var/lib/rabbitmq
          readOnly: false
        - name: config-file
          mountPath: /config/
        - name: plugins-file
          mountPath: /etc/rabbitmq/
      volumes:
      - name: config-file
        emptyDir: {}
      - name: plugins-file
        emptyDir: {}
      - name: config
        configMap:
          name: rabbitmq-config
          defaultMode: 0755
  volumeClaimTemplates:
  - metadata:
      name: data
    spec:
      accessModes: [ "ReadWriteOnce" ]
      storageClassName: "standard"
      resources:
        requests:
          storage: 50Mi

and service

apiVersion: v1
kind: Service
metadata:
  name: rabbitmq
spec:
  type: LoadBalancer    
  ports:
  - protocol: TCP
    port: 5672
    targetPort: 5672
    name: amqp
  - protocol: TCP
    port: 4369
    targetPort: 4369
    name: discovery      
  - protocol: TCP
    port: 15672
    targetPort: 15672    
    name: management
  selector:
    app: rabbitmq