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

What support options do you offer?
In order to keep costs down we provide technical support and remote assistance via trouble ticket...
Am I completely anonymous with LiquidVPN?
LiquidVPN is a privacy service. It is important to note that by design a VPN does not provide an...
How fast are your VPN servers?
LiquidVPN only runs dedicated baremetal servers with 1 Gbps or 10 Gbps ports. We only use premium...
What kind of encryption does LiquidVPN use?
LiquidVPN implements the highest level of encryption natively supported by each of our VPN...
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...