Wow, that's a good news. Then we dont need worry for auto debit where need to always take care of account. haha

i remember correctly, someone swiped more than available balance, but that only worked for one time. next swipe, did not go thru because credit already -ve.

also, we dont know if bigpay has a limit/threshold to allow this to go thru (if possible), especially your example -- rm1k swipe with rm100 balance. maybe there is a small-ish % allowance to over-swipe.