Contact AGL directly. They will sort this out for you.You may have to stop the "Bill Smoothing" though. It seems that AGL like to keep a large buffer for the bill smoothing. Bill Smoothing is a good idea but you can achieve a similar thing by stopping the bill smoothing and organising a regular direct payment to AGL through you online banking. That way, when you are in credit you just stop the regular direct payment until you use the credit up.