Which is a big flaw, if you ask me. You have have to do the extra step, login as reseller, create the account there, and now the customer has THIS reseller as provider. There needs to be a way for the admin to change the customer from reseller a to reseller b and so on...
Also, while doing an upgrade from 9.x to 10.x, if you create a customer, you HAVE to define a abbonement (domain) which is created during this process, which makes no sense to me. I want to create customer's but assign them domain (abbonements) later, which is not possible actually.