A Line item selector in Punchh is typically a list of SKUs that will be eligible for some kind of discount. In the qualification criteria for discounting, the LIS becomes the filter applied (line item filter) when calculating the Punchh discount.
If 0.00 priced skus end up in the line item selector and line item filter, set up to discount by quantity for example, you run the risk of your discount not applying correctly because Punchh will find the first item in the list to apply the discount to, and process that amount. If the amount is 0.00, no discount will be applied.
For example, if you are going to discount exactly 1 item in a LIS and the first item on the receipt is priced at 0.00, that will be the item discounted, and no discount will be applied. For that reason it is best not to include 0.00 line items in line item filters in Punchh
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