I'm getting this error message: Browser Caching is not

Hi,

I'm getting this error message:

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 contacted my host and they said the 'expires' module is enabled.

Can you help?

Regards,

Ashley