It says that the closing main tag should come after the second closing paragraph tag, and it is! It’s still wrong!
What I have now is:
<main>
<p>Kitty ipsum dolor sit amet, shed everywhere shed everywhere stretching attack your ankles chase the red dot, hairball run catnip eat the grass sniff.</p>
<P>Purr jump eat the grass rip the couch scratched sunbatheshed everywhere rip the couch sleep in the sink fluffy fur catnip scratched.</P>
</main>
Many strings in the HTML syntax (e.g., the names of elements and their attributes) are case-insensitive, but only for uppercase ASCII letters and lowercase ASCII letters. For convenience, in this section this is just referred to as “case-insensitive”.
The test is just not set up to handle it. Which is probably for the best just to teach best practices. You should keep your HTML tags/elements to lower case.