Overpayment letter from the unemployment office - 3 weeks in

I received a letter saying I was overpaid about $700 on my claim. I have read a lot of threads here and could not find my exact situation. The letter mentions an appeal window and a repayment plan. Who should I talk to first?

Read the letter for the appeal deadline and act on it, even if you think you will end up repaying. Then ask about a payment plan.