Tell us what’s happening:
When i check out the link:

it gives an example code of the rest parameter with n1, n2, n3
being replaced with …n
why doesn’t the same logic aplies to the lesson?
And can’t we use x, y z
to …z?

Things I tried to make any scense of it so far is:
As far as i understand it it replaces and stores the values
but is limited to only the ammouth of variables you have
a and b does not exceed this logic so thats not the problem

Your code so far

const sum = (...z) => {
return args.reduce((a, b) => a + b, 0);
}

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Challenge: Use the Rest Parameter with Function Parameters