That's ok. Sometimes there are multiple possible ways to say something. The exercise might choose to use a different possible answer than what is shown as the translation. There isn't one exact answer, so you have to figure out what possible answer you can make from the tiles provided.
Mine only gave "Aloha" "Aloha kaua" and "E". I naturally chose Aloha kaua since it's the only one with a pronoun--but Aloha was the answer. It's a little too vague to have "Aloha" (a very broad word) for a specific answer. That's like giving "Lei" and expecting the user to input "Wearing a lei"
my only options were 1) aloha, 2) aloha pono, and 3) aloha kaua. I chose "aloha kaua" and it said the right answer was "aloha."
Ugh, if you want people to learn correctly than there should be an option for the "correct" answer. It's kākou not kāua.