You can cancel your Domestika PRO subscription directly from your profile. You only have to access the Domestika PRO section within your account, you can do it from here.
Once inside you will see the option to cancel your subscription. When you select it, you will be asked for confirmation.
Once you have canceled the subscription, the changes will be saved and it will not be renewed in your profile on the date indicated, so you will no longer be PRO. But don't worry, even if you stop enjoying the benefits of being a PRO at Domestika, you will still be able to access your courses and general content at Domestika.