You are not required to provide a SSN in order to garnishee wages of an employee. In fact, because such data is confidential, it would probably be lucky if you were to have one. If the employer fails to respond to your order, you will need to bring the matter to court. Perhaps before doing that, send a letter to the employer telling it that is your intention. Then use your letter, and their response if you are lucky enough to get one, in your motion to the court regarding the company's refusal to follow the withholding order.
Alternatively, you can notice a judgment debtor exam and get the SSN from the debtor. Then try again with the employer.
Good luck to you.
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A letter would be the best way to start in terms of cost-effectiveness. I agree with Mr. Pedersen.
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