I'm running a remote react server with a NGINX load balancer. When I use HTTP, I have no issues. But when I set HTTPS=True in my react environment, I get bad gateway when I try connecting the webpage.

The NGINX log says the following:

2021/07/06 10:01:07 [error] 10365#0: *62 upstream prematurely closed connection while reading response header from upstream, client: 155.4.218.180, server: _, request: "GET /favicon.ico HTTP/1.1", upstream: "http://10.50.3.152:80/favicon.ico", host: "remdent.com", referrer: "http://remdent.com/"

And 3 more similar messages claiming upstream was prematurely closed. How do I remedy this?