ERR_CONNECTION_REFUSED [nginx,gunicorn]

Hi DO community! I know this question has been asked before many times but do believe I have followed everystep mentioned in answers but nothing works. My website was running very well except when I found out that Multiple image uploads gives 413 request entity too large error and for the sake of solving it I just did the mistake of putting “client_max_body_size 100M;” in nginx.conf. From that time till now my website is not getting open and I am getting:

This site can’t be reached [mydomain] refused to connect. Try: Checking the connection Checking the proxy and the firewall ERR_CONNECTION_REFUSED

I removed the line and restart nginx multiple times but same thing is continuing. I followed this: https://www.digitalocean.com/community/questions/help-me-to-fix-err_connection_refused and many others to solve the error but nothing happens. I have checked out error logs , there is nothing exceptional in them and even now they are not updating to show some new error. I have checked nginx syntax , gunicorn status. Everything is up and fine. Only one thing that I found weird after running this command sudo journalctl -u nginx: failed to read pid from file /run/nginx.pid So I decided to remove this error and followed https://www.digitalocean.com/community/questions/unable-to-start-nginx-failed-to-read-pid-from-file-run-nginx-pid But still nothing is working out. Do help me out as my running website has just stopped that is causing alot of issue to me.