Filter & Action Not working on Divi Child Theme

Hello,

I have this filter inside my Divi-child/functions.php file and it doesn’t seem to work.

Here’s my code.

add_filter("newsletter_message_html", "newsletter_message_html", 10, 3);
	function newsletter_message_html($html, $email, $user) {
	   return str_replace( '{year}', date('y'), $html );
	}

I tried to dynamic the year from Settings-> Message template, can you help me?

Thanks,
Glen