Hi @silviamancii, thanks for getting in touch!
Has the scan ever worked? The error above sounds like it possibly hasn’t, but it can also be affected by you or your host recently turning on extra protection on your server like a firewall, or Cloudflare as a couple of examples. If that seems like the probable cause, you will need to allow your site’s own IP(s). Our IPs are here for your reference too in case you need to allow those:?https://www.wordfence.com/help/advanced/#servers-and-ip-addresses
If applicable, how to allow our IPs in Cloudflare is detailed here:?https://www.wordfence.com/help/central/connect/#troubleshooting-connection-issues
Regardless of whether you’re using Cloudflare, you can discover your site’s IP(s) in?Wordfence > Tools > Diagnostics > IP(s) used by this server?if you don’t already know them.
For IP detection in Cloudflare, our “Use the Cloudflare “CF-Connecting-IP” HTTP header to get a visitor IP. Only use if you’re using Cloudflare.” option is explained here:?https://www.wordfence.com/help/dashboard/options/#general-wordfence-options
Thanks,
Peter.