Overwrite X-Frame-Option on Ghost Site

I’m running a ghost site on DigitalOcean and need to update the X-Frame-Options that seemed automatically added. I run this command to browse through all files:

grep -ri "X-Frame-Options" /etc/nginx

and it turned out that the header was set only in ssl-params.conf. I tried to disable this by adding comment but no change reflected on the front-end. Is there other option to disable this header on my ghost site? I checked config.production.json also but couldn’t find the option.

It might sound simple, but did you reload the nginx config (sudo nginx -s reload)?