is my budgie sick or just a female

So im still fairly new to this website and it took me about 5 minutes to figure out how to start a new post again lol but basically i made a previous post about my worries that my parakeet Maui might have mites because his/her cere WAS a little crusty and what scared me even more was that his/her cere turned a very very deep redish brown color. After a little more research i was informed that female parakeets ceres turn a brownish color when they are ready to breed, i didnt know if this was the case with my parakeet because at the pet store i got maui and his/her brother lazuli from the lady told me they were both males. Also his/her cere is no longer as crusty as it was and is definitely smooth now but is still a very deep red/brown. Hopefully i can figure out how to post a picture on here so i can get some feed back, also in the picture i will try and attach you can see that Maui has some areas around the top of his cere where there is a lack of feathers should i be worried about that as well? Please let me know if i correctly attached the photo because im new to this (ALSO if Maui is a girl how long will her cere be that brownish redish color?and should i separate her and Lazuli?)

She is female and you don't have to seperate them

Yep female, no health issues or mites