Ever since they switched to the user contribution system (no doubt so they can produce languages faster; quantity vs quality) I've noticed a lot of inaccuracies, sloppy testing structure, etc. All you can do is flag the question for review for someone to take a look at it--hopefully Duolingo staff, not the original writers.
I won't always be using the diacritical markings of glottal stops (okina) & macrons (kahako) in my written responses, therfore I will probably continue to receive "scoldings" by Duolingo for not including them. Olelo Hawaii is an oral language. My ancestors did not get hung-up on using them when WRITING the language. Diacriticals are a modern-day tool employed to help with pronunciation. Let's not get too reliant on or be a slave to them!
This is a course for beginners, though. It is designed just as much as books like Na Kai Ewalu and Ka Lei Haaheo to teach the language. Thus, it starts in the same way - with diacritical marks to guide in pronunciation. It is not designed with the assumption that people with prior knowledge of the language will use it according to their realm of knowledge of the language. O ia ko‘u wahi manao.
Aloha Alika, If you are using a computer keyboard, press the "fn" button in the lower left corner of the keyboard, then press the vowel at the same time until a line of options appears on the computer screen for your vowels, release the "fn" button and the vowel button, see the numbers under each of the vowel variations and press the number under the vowel with the kahako. Mine is number 6.