I owe an outside agency 871.00 for unemployment overpayment will it cause an offset to my current return and if so how long will it be delayed?

I filed my taxes on 2/08/2018. On 02/12/2018 I checked WMR and the bars were gone and it just says your refund is still being processed. A refund date will be updated when available...(may not be exact words). I called today and the guy from IRS says to wait a couple of more days since it have not quite been 3 weeks yet. He also said that he see's that I owe an outside agency and gave me a number to call. I called found out I owe 871.00 to unemployment for overpayment. I would like to know if this will cause an offset and if so how long will it delay the rest of my return. I also would like to know if I did not file 2016 taxes yet will that also delay my 2017 taxes?