Hamchi Reyal Tunnel (blue dot)

Our clients are having trouble to connect to there server via Hamachi. They are experiencing a relay tunnel (blue dot). We have changed the Local UDP and TCP Address to 45565 and 45566, allow Hamachi through the firewall and anti-virus, restarted the Hamachi2Svc service in Task Manager and uninstall and reinstall Hamachi. Our clients are running a 50Mbps upload and download fibre connection. What else can be done to turn the relay tunnel into a direct tunnel?