Got an overpayment notice, what now? - what worked for you?

I received a letter saying I was overpaid about $1050 on my claim. I have been trying to stay organised about it. I did not notice any errors at the time. Has anyone disputed one of these?

Read the letter for the appeal deadline and act on it, even if you think you will end up repaying. Then ask about a payment plan.

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.