Contact your bank again. Ask if it is a "child support lien" or a writ of garnishment? Most likely the bank received a Writ of Garnishment, which is an order from the court telling the bank to freeze the account and to file a paper with the court stating how much money is in the account. Ask the bank employee to tell you the case #, the court name and number (example 14th District Court of Dallas County or Dallas County Civil Court at Law # 4). If the bank employee is really helpful they may make a photocopy for you of the papers that were served on the bank.
After you find out which court issued the garnishment, and the case number, then contact the clerk of that court and get copies of the Final Judgment and the Petition in the case. If that seems to difficult to do, then retain an attorney to do that for you.
You need to find out why this is happening, and if it is due to a judgment against you, then you may need to act quickly to file a motion for new trial to set aside a default judgment. To do this you need to hire an attorney. Another possibility is that you account was wrongfully garnished (because the judgment is not actually against you) and to investigate this possibility you need to get copies of the relevant papers from the court clerk's file, including the judgment.
Once you know more about what you are dealing with, you (or your lawyer) can file a Motion to Dissolve Writ of Garnishment, which would be heard by the same judge who signed the judgment. In this motion you make you arguements as to why your account should be released. Usually such a motion qualifies for an "emergency hearing" meaning a hearing as soon as three days after you file it.
I suggest you retain an experienced attorney to investigate this matter for you and then advise how best to deal with it.
