To cancel your subscription click the VPN Administration button on the left hand menu of https://my.liquidvpn.com/clientarea.php 
Click VPN Administration 
Click the service you want to cancel
Click Request Cancellation
Choose to cancel immediately (takes up to 24 hours to process) or at the end of billing period
Either option will stop your subscription before being billed again.

Also Read

Do you offer TCP and UDP OpenVPN connections?
Yes, and we provide several ports for each type of network topology we offer.
What kind of encryption does LiquidVPN use?
LiquidVPN implements the highest level of encryption natively supported by each of our VPN...
Will LiquidVPN work with my router?
Because we offer OpenVPN, PPTP and L2TP LiquidVPN should work with most routers. Routers with the...
Can I use LiquidVPN instead of my ISP?
No, a VPN works in conjunction with your internet connection. It cannot be used to replace your...
Can I use LiquidVPN on a mobile device?
The short answer is yes However we have not released our mobile VPN client yet so you will need...