oliviaontheriviera on "[Theme: Spacious] Change Read More button language + Footer theme name"

Thanks for your reply,
Found this in the codex page => Modify The Read More Link Text
Adding this code to your functions file enables you to customize the read more link text.

add_filter( 'the_content_more_link', 'modify_read_more_link' );
function modify_read_more_link() {
return '<a class="more-link" href="' . get_permalink() . '">Your Read More Link Text</a>';
}

I added it to the child theme functions.php file at the end but it doesn't work. the code just appeared on the website. Any idea what I'm doing wrong?
Thanks