How to disable SSL checking on Nginx?

I have some QA server for my website.
A year ago I’ve tried to make SSL connection to my production website so I’ve implemented it on the QA by nginx too.

Now it’s expired and I don’t want to renew it on the QA.

How can I do it without removing Nginx.
I’ve tried some things that I’ve googled but I didn’t find something good.

It’s still demanding the SSL checking, and this is the error that I’m getting when I’ve tried to load it:

    main.9b8be0e9.chunk.js:1 Mixed Content: The page at 'https://example.com/' was loaded over HTTPS, but requested an insecure resource 'http://example.com:46/ws/....'. This request has been blocked; the content must be served over HTTPS.

The nginx start of configuration…

server {

listen 80;
#some trying
ssl_protocols TLSv1.2 TLSv1.1 TLSv1;

server_name mydomain.com www.mydomain.com;
#I remove the s from the https...
return 301 https://example.com$request_uri;

}

I also have listeners on the port of the server and 443