Depends. Did you enter into a written agreement to that effect? If so, then no. However, if he filed an action and served you but you did not answer, then he may have legal grounds.
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An agreement concerning enforcement of a court judgment must specify whether or not the creditor is going to forgo wage garnishment in return for voluntary payments. Hope the agreement you have is in written because it is often said a verbal agreement isn't worth the paper it is written on.
Court judgments go on your credit report as a public record. You can't remove them & this information will remain on your credit report for a long long time. Hope this perspective helps!
I would politely tell him that he can begin garnishing your wages but that your offer still stands, and if he will accept payments in lieu of garnishment, then you prefer that.
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