To prevent discount stacking, the NA Bulk Price Editor app can block discount codes
When the discount code block setting is enabled, customers will not be able to enter discount codes when their cart contains any item affected by the price change job.
IMPORTANT: The discount code will not be applicable to any of the items in the cart, including items that were not affected by the price change job. This is a limitation of how Shopify allows apps to block discount codes.
When the price change job is reverted, the discount code block will be lifted. NA Bulk Price Editor also allows you to unblock discount codes from a stand alone action (if want to allow discount codes, but don’t want to change prices back)
Under the Discounts section of Shopify, you will notice the automatic discount that NA Bulk Price Editor creates to block discount codes
You can deactivate or delete the app automatic discount if necessary, but it is recommended to unblock discount codes through the app when possible.
Each price change job will add its own discount code block. This means that if there are two price change jobs that block discounts that are both active for the same product, reverting or unblocking the discount on one job will not allow discounts to be used on the product. Both price change jobs would need to be reverted or unblocked for the discount code to be allowed again.