This could mean the same as "onde você tem dormido?" = "where have you been sleeping?".
(Suppose someone is new in town and has no home yet)
Or it could mean "qual é a sua cama" or "qual é o seu quarto" = "which is your bed?" or "which is your room".
(Suppose you just arrived in a vacation house where your friends have arrived first)
Of course those aren't translations, those are different sentences that could have the same meaning in a specific context.
If we are going to be pedantic about progressive forms of stative verbs because "they don't make sense" then this sentence needs to be "Onde você vai dormir" because it can't be an ongoing action or else the person addressed will not answer the question.
This is really one of the failings of this program. It breathes your neck about "proper usage" sometimes and then turns around and gives you a translation that only loosely follows grammatical rules, if I am being generous.