Generally, your credit card account agreement advises that you must cancel all agreements for pre-authorized transfers or pre-arranged charges by merchants prior to closing an account.
In many cases, the credit union does not cancel these for a simple reason: the pre-authorized withdrawal agreement was made between the consumer and the merchant making the charges. Since the credit union is not a party to the agreement, it cannot cancel it. Therefore, the withdrawals can be charged to the account even after the consumer has closed it.
You can stop the credit union from paying a single pre-authorized charge by contacting it in writing or orally, at least three business days before the pre-authorized charge will be made. However, this may not cancel your agreement for ongoing pre-authorized charges with the merchant. The credit union can require you to submit written confirmation that you have cancelled the agreement with the merchant within 14 days of your contact with the credit union, telling it not to pay the pre-authorized charge. If you do not provide the credit union with written confirmation, it may honor any following pre-authorized charges by the merchant.