Were you using ACH (i.e. your routing and account number) for payment? To be honest this feels more like a problem of ACH rather than of Amazon. The antiquated ACH system really isn't built to deal with real time e-commerce applications.
To avoid this problem in the future, always use credit card to pay for things whenever it's an option. When it's someone else's money at stake, you can sleep better at night :)
To avoid this problem in the future, always use credit card to pay for things whenever it's an option. When it's someone else's money at stake, you can sleep better at night :)