A merchant using Square POS synced with Shopify needs to offer customers a choice between tinted and non-tinted sunscreen within a 6-product skincare bundle. The bundle is managed as a single SKU in Square, which automatically deducts all 6 items from inventory when purchased.
Proposed Solution (Confirmed by Community):
Create two separate bundle SKUs in Square: one for non-tinted sunscreen, one for tinted
Set up a single bundle product in Shopify with two variants, each mapped to its respective Square SKU
This approach maintains accurate inventory tracking while allowing customer selection
Current Issue:
After implementing the suggested setup, the merchant encountered an inventory sync problem. When entering the SKU for a variant, Shopify displays an error: “Already used by 1 other item.” The merchant cannot locate this duplicate item in their system, and updating the SKU or product name affects both the original and the phantom duplicate. Shopify support suggested deleting the extra product, but it cannot be found.
The discussion remains unresolved with the merchant stuck on this technical sync error. A screenshot was shared showing the SKU conflict message.
Summarized with AI on October 24.
AI used: claude-sonnet-4-5-20250929.
I need some helping figuring out the best way to handle my bundle situation.
My inventory is managed by Square (we use Square POS for in store purchases) and that data is synched with Shopify for online sales.
We built one SKU in Square that includes 6 skincare products as one bundle. So if someone buys the bundle, all 6 items are subtracted from inventory.
5 of these products never change and have no variations.
The 6th product is a sunscreen and it’s currently set up so if they buy the bundle, they get a non-tinted sunscreen.
We would like to have this bundle set up so that they can select tinted or non-tinted sunscreen.
I’m thinking the best way to handle this is to set up a second SKU in Square that is the bundle but the only difference is it’s a Tinted sunscreen.
Then I’d set up a variant on this product.
One variant would be the non-tinted with that SKU for that bundle
One variant would be the tinted with the new SKU for that bundle.
Easiest fix: create a second SKU in Square for the “bundle + tinted sunscreen,” then set up both bundles (tinted/non-tinted) as variants of the same product in Shopify. That way, Square tracks each correctly and the right items are deducted from inventory.
If bundles get more complex later, consider a bundle/inventory sync app but for this case, two SKUs mapped as variants is the cleanest.
I was able to set up the product as you all suggested, but the problem now is that the inventory is not synching. In the area where I put the SKU for the variant, it tells me “Already used by 1 other item.” but it’s the exact same item with the same SKU that doesn’t exist. I tried asking Shopify for help and they told me I should delete the extra product. BUT it doesn’t exist. I can’t find it. I’ve tried updating the name of product and its SKU but when I do that, it updates the SKU for the duplicate also. So I’m stuck.
