In the Shopify App Store, there are several apps that can help you create personalized codes, create bulk discounts, or volume discounts for promotions. Unfortunately, Gift Box does not work properly with these discount apps since Shopify doesn't allow combining more discounts together, and free gift is always considered a discounted product.
Unfortunately, the technical solution of our app has limits imposed by the Shopify platform's restrictions. This has been discussed with Shopify developers for years, so hopefully they will give us more freedom in terms of discounting in the future.
On a side note, you can still use our app with additional discount codes.
As Gift Box uses draft orders, this will allow you to input certain discount codes you create in your Shopify admin to get discounted prices of your products. For more information, please visit How to enable discount code with free gift(s)?
Alternatively, there are other gifting apps that are built on a different basis and could be a better fit for your business in certain cases: