Alternative ways to spend minutes?

Hi, I could not find any contact info/help section so I am writing here
I have not been using renderjuice for several months and i recently canceled my credit card i used for billing. When I opened my account yesterday after a long time, i could not see my credits since my last payment was unsuccessful.

I want to unsubscribe since i do not need rendering services right now but I want to use my accumulated credits in the future. How should this work?