Overpayment letter from the unemployment office - what worked for you?

After 14 weeks of benefits I got a notice saying I must repay some of it. There are 17 people counting on me, so I am trying to be careful. 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 10 months ago, and it got easier once I kept a simple log of every call and form.