Multiple cart items of different type
By default, the theme will allow you to have only one cart item. You can easily change this by add the following code into your child theme’s functions.php file:
add_filter( 'routiz/cart/empty_cart', '__return_false');
Multiple cart items of the same type
If you also want to enable multiple cart items of the same type, you need to edit the product type and change this. For example, if you want to have multiple plans, then edit the following file:
\routiz\inc\src\woocommerce\products\wc-product-listing-plan.php
and change is_sold_individually to false, like:
public function is_sold_individually() {
return false;
}
You can find all the product types in the same folder:
\routiz\inc\src\woocommerce\products\