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6. Alternative flows
Customer present presents the coupon code along with the products that they want to buy purchase at the cashier
Cashier then proceed proceeds to add items to cart by scanning barcode/searching/selecting products in the POS frontend.
Cashier selects Discount and enter the coupon code and click Apply. The POS automatically apply the promotion to the shopping cart of the customer based on the cart price rule associated with said coupon code.
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