Your code looks correct so far. well done! You are right that border-bottom is needed here. There was a mistake in the assessment description, and it sounded like it was asked for border, but the screenshot of the expected result only shows a bottom border. I’ve edited the text so that now it says “Remove the bullets and add a 1px grey bottom border…”
There is one more small thing missing from your solution — the assessment says “Remove the bullets”, but you’ve not done that yet. What CSS property would you use to do that?