Child support is retroactive to the date of filing. If you didn't file a modification petition at the time that you became unemployed, you can't get a refund retroactively. If your still unemployed, then file a modification petition seeking to reduce your child support obligation.
Your only remedy was to seek a modification of support at the time of your unemployment. Even if you do move to modify the support obligation now, it would not be reduced retroactively.
The above answer is intended for informational purposes and is not legal advice. It does not constitute the creation of an attorney-client relationship.
Child Support paid previously is non refundable. You can sue the recipient directly. The chances of winning are pretty small however.
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