Unable to curl httpbin from curl pod

Hi I am new to istio. Below is my istio version details

client version: 1.7.4
control plane version: 1.7.4
data plane version: 1.7.4 (5 proxies)

I have installed istio in my kubernetes cluster. I have deployed two sample pods httpbin and nginx pod. I am trying to curl from nginx pod to httpbin pod.

kubectl exec -it nginx-v1-d5cf9d46-9dct4 -n demo -- /bin/sh
Defaulted container "nginx" out of: nginx, istio-proxy, istio-init (init)
/ # curl httpbin:80

But I am getting the below error.

* Connected to httpbin ( port 80 (#0)
> GET / HTTP/1.1
> Host: httpbin
> User-Agent: curl/7.64.0
> Accept: */*
< HTTP/1.1 503 Service Unavailable
< content-length: 84
< content-type: text/plain
< date: Wed, 10 Nov 2021 06:06:20 GMT
< server: envoy
* Connection #0 to host httpbin left intact
upstream connect error or disconnect/reset before headers. reset reason: local reset

I don’t know why this error is coming up. Do I need to setup anything extra like authetication policy or destination rule ?
Please help me to resolve the issue.