Overpayment letter from the unemployment office - first time posting

After 21 weeks of benefits I got a notice saying I must repay some of it. I cannot afford to repay it all at once. Has anyone disputed one of these?

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

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.