I have attempted to activate Browser Caching. Receiving

I have attempted to activate Browser Caching. Receiving error:
Browser Caching is not working properly:
- Your server may not have the "expires" module enabled (mod_expires for Apache, ngx_http_headers_module for NGINX)
- Another plugin may be interfering with the configuration

I have confirmed that mod_expires is running and Apache was restarted. .htaccess has the appropriate code. At the top of the page it does say... Your browser caching is already enabled and working well, however the error remains so i am discounting this message. Not sure where to go from here.