Submit a domain renewal by following these steps:
How do I renew my domain?
http://www.dynadot.com/help/question.html?aid=70
During the checkout process, the system will ask you what payment method you want to use for the renewal. If you have account credit available, it will ask you if you want to use account credit for this order. If you have enough account credit to pay for the order, you will be led to the order submission page.
However it still would be nice if they took this into consideration when working out total spend. I've spent over $700 with DynaDot but they only recognise $250 of it.
Poor Form and stops me from moving more domains here
Can i pay with parking