Crazy hints! I entered "I have absolutely nothing" then wondered if I should change it to "I have nothing at all" to keep duo happy, so I hovered over the hint to make sure and changed to to "completely nothing" as that was the only hint given. Wrong move :/ Not sure it is worth a report as "I have completely nothing" does sound a little strange, although it is correct.
Because “completely nothing” and “totally nothing” simply aren’t English. It isn’t correct to use completely or totally with nothing. “Absolutely nothing” is correct English. The problem here is, you are supposed to be learning Dutch so if “completely” is one of the hints or translations provided by Duolingo, then you are understanding the sense of the Dutch words even if your answer is not completely fluent as far as the English language is concerned. It is a bit annoying for non native English speakers, I can see that.