Good point about birds sometimes having a comb type that does not match the description.
Yes, I agree that this bird is definitely tricky to figure out.
If it does turn out to be female, we may get a clue from what color eggs it lays at maturity. (At 3 months, a female *might* have that much...
https://www.hoovershatchery.com/prairiebluebellegger.html
Hoover's description says Prairie Bluebell Eggers have pea combs. The photos on Hoover's page also show chickens with pea combs.
But I am pretty sure I see a single comb on OP's chicken in the first post. (A frontal view of the head...
Do you remember what color it was as a chick?
Black Star chicks are supposed to be black (at least mostly-- they can have lighter color on the underside, rather like a penguin.)
If the chick was yellow, red, brown, striped, etc. then that also shows it cannot be a Black Star.
Hold it, was it...
Not a Black Star, and doesn't look like a pullet.
I'm not sure what it is, maybe a mix of some kind. Mixes sold by hatcheries usually have some kind of special name or purpose: Easter Eggers, Red Ranger, Calico Princess, etc. If it came from someone's backyard flock, it might be a mix without...