Bundle Builder will monitor the available inventory for all products in your bundles if the inventory management is set to Shopify. The app will ensure the number of available bundles is in line with the number of products available, so the bundle can only be purchased if there are enough products in stock. Read Shopify's guide on inventory tracking
As soon as a customer purchases a bundle, the inventory of all related products is decreased, thus preventing other customers from purchasing the same products.
When an order is cancelled, the inventory will be increased back to its original state.
If you run into any inventory-related issues, please send us an email containing the following information:
Any relevant backend variant links from the problem bundle
Any useful screenshots