Error 414 - URI too long

We are using kubernetes/nginx , jenkins. I have a URI that is 8192 long approximately.
nginx is rejecting the query with 414 URI Too Long . I can see the request in the system logs and pipeline is not initiated.
I have tried to update the nginx configuration using config map, but no luck. I have added below params -

client_header_buffer_size 5120k;
large_client_header_buffers 16 5120k;
 When I add above , my nginx-pod is not getting started(crashloopbackoff)error.

I’m not sure how this is a jenkins question. Or a question at all. that seems like a insanely long url, i would recommend taking all the data and posting instead of having it in the url.

In jenkins pipeline-stage, a callback(POST request) to some-repo with (URL+params) is being sent/done. Is there any ways where jenkins/nginx server can handle long uri path? till 8k length its working fine.