Told I owe money back on my benefits (Atlanta)

The agency says I reported earnings incorrectly, but I think I followed the instructions. Thank you in advance. The letter mentions an appeal window and a repayment plan. Who should I talk to first?

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

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