My elderly brother had a failed renewal of his plan - through no fault of his. I presume some glitch in the bank transaction caused the failure. The card details were correct and valid. 

My issue is that within minutes his service was cut off. Surely this is unreasonable - I would expect at least a second attempt at the transaction.

So is there anything we can do to prevent a recurrence of the problem? Would buying extra credit help to keep him on the air?