Incognito or private mode http requests

I have a NGINX based web server, which redirects http requests to https.When I hit the URL in incognito mode, it doesn't load the http page until page is loaded by https. Then http too works after.

Wondering why very first time http not able to load the web page in incognito mode. In regular browsing it works fine.

Any NGINX config to be set?

nginx version: nginx/1.16.1