This must be idiomatic usage because Benutzer is given in two dictionaries as the translation of 'user', also 'Benutzer is feminine, whilst on Duolingo 'Nutzer' is Masculine. Both dictionaries are 2012, one 'Collins' the other 'Oxford', so I think an explanation from Duolingo would be useful.
Both Nutzer and Benutzer mean user and the native speakers I know have struggled to come up with examples where one could be used but not the other.
You can confirm this be checking the translation of Nutzer in your preferred dictionaries.
I should also point out that both Nutzer and Benutzer are masculine nouns.
Yes, the english has nasty drug use conotations now - Duolingo could make it clear that the same meaning does not pertain to German.
I think "Nutzer" would be used in IT (like a program user), while "Benutzer" has much wider meaning. But I am not sure.
Actually I'm not pretty sure if Nutzer is used more by IT people, I do work in IT with SAP system, and always when I'm on the log on window, it appears to me "Benutzername". Maybe it's the opposite?
I don't do much German IT, but I've only ever seen "Benutzer". The word "Nutzer" suprised me here.
Can someone tell me then what does it mean when used in this frase "Nutze den Tag" (carpe diem)
If Nutze den Tag=carpe diem, I can see the relationship between Use the day & seize the day (use it well; take charge of it). Does that help?