Kubernetes cluster output response is getting lost

Cluster information:

Cloud being used: -
Host OS: Ubuntu

I have a k8s cluster which is having a python django server. From my localhost if I hit with a curl request to the cluster, I receive all the responses

seq 1 100 | xargs -n1 -P 40 curl --location --request POST 'http://lcluster_address7000/api/v1/test' --form 'name="abc"' --form 'version="2"'

This will send 100 requests with 40 request in parallel. Lets assume the endpoint just sleeps for 5 seconds and returns random string. With the above curl, i am getting all the 100 responses.

I also tried, having a python flask server in my local,

seq 1 100 | xargs -n1 -P 40 curl --location --request POST 'http://localhost:500/test' --form 'name="abc"' --form 'version="2"'

The above curl will send request to my local flask server which will call ‘http://lcluster_address7000/api/v1/test’ using requests python library. In this case all the 100 requests where sent to cluster, and the server on cluster is returning 200 status code but response is not received in flask server in my localhost.