Overpayment letter from the unemployment office - 13 months and counting

I received a letter saying I was overpaid about $500 on my claim. I have read a lot of threads here and could not find my exact situation. I cannot afford to repay it all at once. Who should I talk to first?

I asked for a waiver and a plan in the same call, and they gave me both forms. It was less scary than I expected.