The add-on feature at checkout currently does not track inventory for the products that are added to it. So, if an item is sold out in its listing, people can still purchase more of it through the add-on at checkout unless you manually go into each listing and remove it from being an add-on. It’s the worst and caused a lot of problems during holiday sales.
Hello @Winsomeparcel, I appreciate you reaching out and bringing this out our attention. I am sorry this happened during the holidays and certainly want to make sure this gets resolved. To get a better idea of what you are referring to is there anyway you can provide a some screenshots or video of the issue with the add-on feature, and what is going on? If our team does need to file a ticket they will ask for more details like this as well. I will keep an eye out for your reply.
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