If you get an error message saying 'The registered e-mail is registered on a payment plan which is not supported for resellers', then it is most likely because the account you are trying to sign-up with is not a Premium account.
This could be because you have just opened a Cookiebot account or because you have an account that is currently on a 'free subscription'. In order for us to sign you up and convert your account to a reseller account, it must be a Premium account.
Here is how to fix it:
1. If you already have a Cookiebot account, sign in: Cookiebot manager
2. On the page 'My account' (at the top right corner) – or in the top menu – choose 'Upgrade to Premium Subscription'
3. Follow the instructions and register your payment details (credit card or PayPal).