Check what you do inside your while and after it. You have to change that part at least for it to work.

The first thing I see wrong in your code is the function definition: def find_missing (list): change list for a there. Then read the description again carefully, you're overcomplicating things.

Please, when posting code use markdown formatting otherwise all indentation is lost and in Python, where it matters, your code becomes hard to read.

You need to return the function call to narc inside narcissistic. If there is no explicit return in your function, the default returned value is None.
To increase the readability of comments or descriptions, see this page in the github wiki.

Are you calling that function from inside narcissistic function?

You're printing the output instead of returning it.