Readiness Probe Failed & Connection Refused Inside Kubernetes

I have prepared some basic example of Keycloak inside k8s , where I have a problem that when I deploy Keycloak Helm Chart in the end of deployment I have such an error:

  Normal   Created         3m56s                   kubelet, oauth2-proxy-control-plane  Created container keycloak
  Normal   Started         3m56s                   kubelet, oauth2-proxy-control-plane  Started container keycloak
  Warning  Unhealthy       48s (x16 over 3m18s)    kubelet, oauth2-proxy-control-plane  Readiness probe failed: Get  dial tcp 10.244.0.9:8080: connect: connection refused

$ kubectl get pod -o wide

NAME                                READY   STATUS    RESTARTS   AGE   IP            NODE                         NOMINATED NODE   READINESS GATES
oauth2-proxy-example-0              0/1     Running   3          8h    10.244.0.9    oauth2-proxy-control-plane   <none>           <none>
oauth2-proxy-example-postgresql-0   1/1     Running   1          8h    10.244.0.10   oauth2-proxy-control-plane   <none>           <none>

What is wrong with config and why it can't check readiness probe?

UPDATE

  readinessProbe: |
    httpGet:
      path: /auth/realms/master
      port: 9080

And now I get:

  Warning  Unhealthy  83s (x2 over 93s)    kubelet, oauth2-proxy-control-plane  Readiness probe failed: Get  net/http: request canceled (Client.Timeout exceeded while awaiting headers)