How many companies train on data that contains 'i don't know' responses. Have you ever talked with a toddler / young child? You need to explicitly teach children to not bull shit. At least I needed to teach mine.
The "dunno" must not be hardcoded in the data, it must be an output of judgement.
You have an amount of material that speaks of the endeavours in some sport of some "Michael Jordan", the logic in the system decides that if a "Michael Jordan" in context can be construed to be "that" "Michael Jordan" then there will be sound probabilities he is a sportsman; you have very little material about a "John R. Brickabracker", the logic in the system decides that the material is insufficient to take a good guess.