"You have the coffee."
'Sende kahve' was wrong. Why is that? Does that change the meaning of the sentence?
No. You could say "sizin kahveniz var" and that would mean "you have coffee"
Nope..."coffee" is actually the subject of this sentence in Turkish.
Spanish and English and more popular languages have less bugs. Kahveyi should be right.the i ending.(the)=i ending in some words.
this is no bug/mistake, maybe try to ask why it is like this in order to learn :)
The problem is that Duo previously used "the" in English translations to signal accusative case. This sentence would have been fine to present in English as "You have coffee"