- Some DNS servers haven't yet updated the records (it depends on TTL), and not all traffic has been redirected to Gcore for filtering. You need to wait.
- You haven't changed your real IP address to a new one after you had enabled DDoS Protection. It means that an attacker knows it, so you need to request a new IP address from your hosting.
- You haven't restricted access to your server. Contact your hosting provider or use a firewall to set up ACL.