Hello @iagoditu
I am sorry about the issue you are experiencing and I am happy to assist you with this.
I’ve installed the mentioned plugin along with the W3 Total Cache. Once activated it added the rules in the .htaccess file just below the W3TC rules, and there were no problem with the security headers.
W3 Total Cache also has Security headers option in Performance>Browser Cache>Security headers section.
Please make sure that those options are disabled, and if the issue persists, disable the settings one by one in Performance>General Settings, save all settings and purge the cache once any setting is disabled and see which one may be causing the problem for you!
Thanks!
Marko thank you! After deactive “Browser Cache” in Performance>General Settings it solved all problem!