First, Please login to VPN Control Panel, and make sure your VPN is active. If all thing with your VPN account status is good, make sure you tried with all protocol OpenVPN, OpenConnectand if you are in Windows with PPTP.
If still there is an issue with connecting, please contact us via the below form:
https://worldvpn.net/billing/submitticket.php?step=2&deptid=2