I have configured a custom domain in my store, but discounted bundles don't work
By default, any Shopify store is published in a subdomain of myshopify.com, such as www.my-super-duper-store.myshopify.com (the canonical domain), but you can link your store to a custom domain such as www.mysuperduperstore.com. There are many reasons to configure a custom domain for your store, but the most important is SEO and branding.
You can buy a domain from Shopify or any other third-party provider, but in any case, we recommend that you take a look at the Shopify Help Center for more details.
Whether you buy a domain to Shopify or a third-party provider, it's essential to ensure that the canonical domain points to the custom domain so that your visitors and potential customers are ultimately redirected to the latter.
Why is this important, and how does it affect Frequently Bought Together?
Suppose for whatever reason, the custom domain is not correctly connected to the canonical domain. In that case, the discounts you have configured in Frequently Bought Together won't be applied because of a Shopify limitation (discounts can only be applied if the storefront and the checkout domains are the same).
To depict the scenario, when your store is available through the canonical domain ( www.my-super-duper-store.myshopify.com) but the checkout redirects to the custom domain (www.mysuperduperstore.com), the widget will fail to add products to the cart when a discount is configured for the bundle. You will see the following message in the widget:
As mentioned before, Shopify does not allow apps to apply discounts when both the canonical domain and the checkout domain don't match.
How can we solve it?
To solve this issue, you should redirect your Shopify domain to your third-party domain, so everyone who accesses your store is always sent to the same domain.
Once you have correctly configured your domains in your Shopify Admin, discounts will be correctly applied, and your customers will be able to add bundles with discounts to the cart in Frequently Bought Together.
If you buy the custom domain to Shopify, the canonical domain is automatically redirected to the custom domain. On the other hand, if you buy a domain from a third-party provider, you will have to connect both domains by following the instructions explained at Connecting a third-party domain to Shopify.
In any case, we recommend that you can contact Shopify Support to help you with that if you need assistance.