Overpayment letter from the unemployment office (update)

After 12 weeks of benefits I got a notice saying I must repay some of it. I am in Little Rock, in case local advice matters. I did not notice any errors at the time. Are payment plans possible?

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

Thanks for writing this out. I went through something close to it 4 months ago, and it settled down once I kept a simple log of every call and form.