No, pre-authorized debits (PADs) cannot be disabled as a default setting on your account. This is not something Payments Canada supports. The best way to prevent unwanted or unauthorized PADs on your account is to only share your account details with people that you trust.
If you notice a PAD on your account which you don't recognize, or you wish to issue a stop payment on a specific PAD going forward, please reach out to our support team via the in-app chat or via email at support@tryvault.com