You cannot cancel a membership from this website. This website just provides instructions for how to cancel. The only way to cancel is from a specific email you received.
A membership doesn't end until you cancel it.
Only cancel a membership if you are sure you want to stop. Once you cancel, it may be difficult or even impossible to restart. Restarting presents the following issues:
All the slots may be taken.
There may be some slots available, but none of the slots work for you.
There is a setup fee.