When you need to cancel your subscription you have to do this into your PayPal account. Depending on if you used a business PayPal account or a personal account here are the two links that will redirect you to the right page.
Business account: Subscription page
Personal account: Subscription page
On that page you need to find Kronozio, when selected you can cancel the subscription. If you have any problem with your subscription please send an email to our support team using this link: Support