400 Request Header Or Cookie Too Large

I am facing some issue with GraphQL contentful api.

StatusCode: 400, ReasonPhrase: ‘Bad Request’, Version: 1.1, Content: System.Net.Http.HttpConnectionResponseContent, Headers:
{
Connection: keep-alive
Access-Control-Allow-Headers: Accept,Accept-Language,Authorization,Cache-Control,Content-Length,Content-Range,Content-Type,DNT,Destination,Expires,If-Match,If-Modified-Since,If-None-Match,Keep-Alive,Last-Modified,Origin,Pragma,Range,User-Agent,X-Http-Method-Override,X-Mx-ReqToken,X-Requested-With,X-Contentful-Version,X-Contentful-Content-Type,X-Contentful-Organization,X-Contentful-Skip-Transformation,X-Contentful-User-Agent,X-Contentful-Enable-Alpha-Feature
Access-Control-Allow-Methods: GET,POST,HEAD,OPTIONS
Access-Control-Allow-Origin: *
Access-Control-Expose-Headers: Etag
Access-Control-Max-Age: 86400
Server: Contentful
Strict-Transport-Security: max-age=15768000
X-Content-Type-Options: nosniff
X-Contentful-Region: us-east-1
Via: 1.1 varnish
Via: 1.1 varnish
contentful-cache: MISS
Accept-Ranges: bytes
Date: Tue, 29 Jun 2021 21:48:35 GMT
Age: 3741
X-Served-By: cache-dca17723-DCA, cache-mdw17372-MDW
X-Cache-Hits: 0, 5
X-Timer: S1625003316.991042,VS0,VE0
X-Cache: HIT
x-contentful-request-id: 21790545-8a31-4807-96f4-bd25d70b4118
Content-Length: 230
Content-Type: text/html
}, responseBody =

400 Request Header Or Cookie Too Large

400 Bad Request

Request Header Or Cookie Too Large
openresty

It does not happen everytime, sometime it works and sometime it does not.

Can anyone help what could be wrong.
Is this could be from Contentful server or Client request.

Any help is appreciated. Thanks,