If technical support cannot be verified, most likely it is due to DNS malfunction. In ISPadmin, DNS servers are located in /etc/resolv.conf. Check their accessibility and functioning, or enter different DNS servers, if needed.

nano /etc/resolv.conf

Malfunctioning web server could be another reason. Restarting it should resolve the issue:

 /etc/init.d/apache2 restart

Another error example is that ISPadmin server cannot contact our server with updates on port 80. In this case, verify communication at IP 95.173.193.60.