Got an overpayment notice, what now? after 17 years as a store manager

I received a letter saying I was overpaid about $750 on my claim. Any experience at all would help. I did not notice any errors at the time. Has anyone disputed one of these?

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.

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