Told I owe money back on my benefits - 18 weeks in

The agency says I reported earnings incorrectly, but I think I followed the instructions. I have read a lot of threads here and could not find my exact situation. I cannot afford to repay it all at once. 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.