It's basically the same with Russian: завтра is like за утра (in the morning).
And look at all the other languages with the same thing: the English "tomorrow" (morrow = morning), German "Morgen" (means both tomorrow and morning, depends only on capitalization), Spanish mañana...
“How soon?” – is my answer “How soon?” – is what Duolingo provides. But, telling me I am wrong. Why? What is the difference? Also, I had similar problem with one other question before. Just checked my notification and got the respond from skstudio . Next time I have to use "Report button" to track an issue.