If you have a paid account, you can cancel it at anytime.
To do so, go to My Projects, select Hosting & DNS, and use the Uninstall option.
Reactivating your website
If you have previously canceled your website, but wish to now bring it back online, you do not need to setup a new Monkey Business Installation. You can simply just reactivate the existing project.
To do so, go to My Projects, select DNS & Hosting, and use the Reinstall option.