Thanks guys,

I imported the math factorial with a different name, so that I could use the default function name in the code solution.

All perfect!

Yes, this could be.

However, note that before trying to submit, I modified the "visible" sample tests from the kata, so that "get_factorial" is called instead of the original function name.

These are the results that I get:

· On "Run tests cases", all are successful
· On "Attempt", 1 out of 16 fails. Output message --> Should throw error

Do you still think this is the problem? I will try to get around anyway.

This returns "-0" if you input zero though.
You should check this case also.