If you can visit your website but cannot visit the control panel, it's likely that your firewall block the connection.

Most office buildings as well as hotels have a firewall setup to block access to the ports required for cpanel, WHM, and webmail to load.

Cpanel port is 2082 and 2083 (ssl). WHM port is 2086 and 2087 (ssl). Webmail port is 2095

You will need to contact network support staff to request access to these ports.