Change "Password Changed" message body

mepr-pw-changed-message.php

<?php
// Copy the lines below this one into a plugin like Code Snippets (run everywhere type)
function mepr_pw_changed_message( $message, $recipients, $subject, $headers ) {
	if ( strpos( $subject, 'Your new Password' ) !== false ) {
		$message = 'This is a modified message'; // Change 'This is a modified message'.
	}

	return $message;
}
add_filter( 'mepr-wp-mail-message', 'mepr_pw_changed_message', 10, 4 );