If you were sued in a credit card collection lawsuit, a Judgment may have been entered against you in Court. The debt collector can use the Judgment to freeze your bank account by serving a Restraining Notice or Marshal's Notice. 
When your bank receives the Restraining Notice, it will usually place a legal hold on all of your accounts held at that financial institution.
The dollar amount restrained will usually be double the amount of the money judgment entered against you in Court. 
Any money deposited into a frozen bank account is subject to instantly being frozen and unavailable for withdraw.
If your bank account has been frozen by a debt collector, don't delay. Once your bank account is restrained, the collection agency lawyers can promptly have the New York City Marshal's Office levy on the accounts by withdrawing your money to satisfy the judgment.
There are many legal defenses that may be available to fight the restraining notice and unfreeze your frozen bank account. These defenses can be made in a court filing called an Order to Show Cause to Vacate Restraining Notice.
Some popular defenses to a restrained bank account include:
Improper or inadequate service of the legal documents
The money in the restrained bank account does not belong to you
You are a joint account holder and the money judgment was only entered against your co-account holder
The money in the restrained bank account is exempt from levy because it is Supplemental Security Income (SSI), Social Security, Public Assistance (welfare), Alimony, Child Support, Unemployment Benefits, Disability Benefits, Workers Compensation Benefits, Retirement Pension or Veterans Benefits. 
 NY CPLR § 5222(a) – "A restraining notice may be issued by… the attorney for the judgment creditor… It may be served upon any person [or business entity]…"
 NY CPLR § 5222(b) – "If a garnishee [bank] served with a restraining notice withholds the payment of money belonging… to the judgment debtor… in an amount equal to twice the amount due on the judgment… the restraining notice is not effective as to other property or money." [ emphasis added]
 See, NY CPLR § 5222(e)