debug_connection doesn't load

events {
worker_connections 65000;
debug_connection << ip here >>
}

#Web Servers
http {
# Def

In order to troubleshoot production issue specific users/clients and avoid having huge debug logs. Need to enable debug for those only clients/users.
this config is in nginx.conf and vhots are in separate files, but still it doesn't load atall, when i try debug in each vhosts config files, the debugs just flow smoothly. Can you help me with this ? troubleshooting for individual requests, nginx 1.16.1 version using.

TIA, Vinay