Overpayment letter from the unemployment office, medical assistant here

The agency says I reported earnings incorrectly, but I think I followed the instructions. There are 7 people counting on me, so I am trying to be careful. The letter mentions an appeal window and a repayment plan. Has anyone disputed one of these?

Keep everything in writing and save the confirmation numbers. It made the follow-up calls so much easier.

Collect your pay stubs and certification records for the weeks they name. Mine showed the error was a date mix-up.