A woman who is afraid of the dark learns that it is not being afraid of the unknown, it is being afraid of the unseen.

Will do better next time =)

You've given us a character and a flaw, and hinted at some of the inner journey (fearing the unseen). What is your character's goal, what is stopping them from achieving that goal, and what are the stakes of failure? Richiev has provided some great ideas.

I'm not seeing a story here. You have only given us a character. The story is what happens to the character.

For instance: "After the lights mysteriously go out in her high-rise apartment. A woman with Nyctophobia must brave the dark in order to find her missing five-year-old daughter."

Now we have a character (a woman afraid of the dark)
A situation (The lights go out)
A goal, (finding her daughter)
And conflict. (She must go into the dark even though she is afraid of it)

You add low batteries in her flashlight and you also have a time frame. she must find her daughter before the batteries run out.

Anyway that is just an example. Your story will be different but I hope you see how I put that together.

Hope that helped, good luck with this!