Nginx auth_request handle saml 302 redirects - nginx

Question

I am using Nginx as a reverse proxy. Also, I am using auth_request feature to protect my resources. For that, auth_request always goes through authrization server where I am using SAML authentication. While authenticating, there is a redirect 302 to IDP (ssocircle in this case) which I am trying to follow at Nginx but I am always ending up with below error:
no resolver defined to resolve idp.ssocircle.com while sending to
client, client: 127.0.0.1, server: , request: "GET / HTTP/1.1",
subrequest: "/saml/login", host: "localhost:9000"
*1269 auth request unexpected status: 502 while sending to client, client: 127.0.0.1, server: , request: "GET / HTTP/1.1", host:
"localhost:9000"
Here is my Nginx configuration:
server{
listen 9000 ;
auth_request /saml/login;
proxy_intercept_errors on;
error_page 301 302 307 = #handle_redirects ;
location /saml/login {
resolver 46.4.112.4 valid=300s;
internal;
proxy_set_header Host $host;
proxy_pass_request_body off;
proxy_set_header Content-Length "";
proxy_pass http://localhost:9090/ ; # url to authorization server
}
location #handle_redirects {
set $saved_redirect_location '$upstream_http_location';
proxy_pass $saved_redirect_location;
}
location / {
root data/www;
}
location /images/ {
root data/ ;
}
}
I tried adding the resolver 46.4.112.4 IP of ssocircle but it didn't work.
Basically, I want to follow the redirect from my authorization server and have user to authenticate themselves at the IDP and return back to the original URL.
I am very new to Nginx. Any help will be much appreciated.
Edit : I am able to resolve the issue stated above. Restarting the Nginx worked for me. But again I am getting this error:
auth request unexpected status: 302 while sending to client,