Products Archive page, how to noindex

I removed it from the google index once but it just comes back

function shop_noindex_but_not_home(){
	if ( ! is_front_page() && is_post_type_archive( 'product' ) ) {
		echo '<meta name="robots" content="noindex,follow" />';
	}
}
add_action( 'wp_head','shop_noindex_but_not_home', 4 );

Where do i put this?

Theme functions.php

Thanks for posting this – I had the placeholder shop page marked as noindex in Yoast SEO, but it’s the product archive that Google indexes.

What would I need to change in the function above if I want to do the same thing but the page is NOT the front page?

The above snippet does just that. It adds the meta tag if it is not the front page.

Nice, thanks very much.