We have certain rules established by the bank, which are clearly stated in this thread (https://bitcointalk.org/index.php?topic=5484771.msg63647081#msg63647081), on our terms and conditions page, and through periodic notifications on our website. These notifications serve as a reminder that multiple declines due to insufficient funds may result in your card being deleted. Your card received a significant number of declines for insufficient funds and was therefore deleted by the bank’s risk control system.