Please logoff from Joker.com, and then visit "Renew your Domains" from the "Domains" menu.
You will then see a "Smimple Renewal", where you can renew any domain with any payment method.
You may also use another Joker.com account, or create a new one for this. Only if you are logged using your regular reseller account, the system always uses the reseller funds for payments.
As an alternative, you also may put only some small funds into your reseller account, just to allow for regular renewal.
Using PayPal instantly adds funds to your account.