How do I make a shortcode to display the shop name on Dokan?

I’m trying to create a shortcode to display the name of the store selling the product on the single product page. However, the shortcode doesn’t show up in the single product page. I am using the Dokan Pro plugin. Here’s the code I have so far, I put it in the functions.php:

// "store name" Shortcode  add_shortcode('storename', 'shortcode_storename');  global $  product, $  woocommerce; function shortcode_storename () { Return get_shop_name ( $  store_user->ID, 40); } 

Thanks