Refund to Credit

[LittleCreek]

If a client purchases a service using the credit on his account how come I cannot refund it to credit? I understand why you might not be able to refund to a credit card or PayPal since the funds did not come from that source. But I should always be able to refund to the credit balance. Now I have to add the credit manually and I cannot even mark the invoice refunded. I don't know what to do with the invoice now.