Schema for products with no GTIN, MPN, or brand

Hello,

Thank you for the follow up.

To fix SKU and availability issue I added a sample SKU to this product(https://www.smallpartsorganizer.com/stackable-storage-bins/bolt-bin/) as shown below:

I also added the code below in your child theme functions.php which fixed the Global identifier issue:

/**
* Filter to add GTIN to Variable Products.
*
* @param array $entity Snippet Data
* @return array
*/
add_filter( 'rank_math/snippet/rich_snippet_product_entity', function( $entity ) {
   if(is_product()){
     $product = new WC_Product( get_the_ID() );
     if( $product->is_type( 'simple' ) ){
       $gtin_value = get_post_meta($product->get_id(),'_wpm_gtin_code', true);
       $entity['gtin8'] = $gtin_value;
     }elseif($product->is_type( 'variable' )){
       $variation = new WC_Product_Variation(get_the_ID());
       $gtin_value = get_post_meta($variation->get_id(),'_wpm_gtin_code', true);
       $entity['gtin8'] = $gtin_value;
     }
   }
   
   return $entity;
});

Please acquire some reviews and ratings to get rid of the aggregateRating and review warnings.

Hope that helps and please do not hesitate to let us know if you need our assistance with anything else.

Hello,

We are super happy that this resolved your issue.

Please let us know if we can mark this as resolved. Do not hesitate to ask if there are any further question(s)

Thank you.