Not able to trace nginx in sentry

I have a nginx container as proxy pass to the api service. The login process goes slower sometime and want to trace the exact cause but the sentry does not track any events associated with nginx (proxy) thus I am not able to figure out if the cause of slowness in login is due to nginx or not because api is fast enough and no issue in there.

Any solution for my problem?

You can play with the logging level in Nginx and look there? You can also enable statsd in Nginx and look at those metrics?