Please know that to create discount coupons we have follow below instruction.
You may create and designate coupons to specific products or product categories under Sales > Coupons.
The Coupons page will display a list of all the coupons created in the administration.
Editing or inserting a coupon will lead the administrator to a form containing the following fields:
Coupon Name: A descriptive name for the coupon.
Code: A code that the customer needs to enter in the shopping cart to use the coupon in the store front.
Type: The discount can be a fixed amount off, or a percentage off from the total amount.
Discount: The number taken off from the purchase total.
Total Amount: The amount a customer must reach before using the coupon.
Customer Login: Selecting 'yes' requires the customer to be logged into their store account to use the coupon. Selecting 'no' will let a customer use the coupon as a guest.
Free Shipping: Selecting 'yes' gives the customer free shipping for using the discount code.
Category: Selecting a product category will apply the discount to all products within that category. See Categories for more information on how to create a new product category.
Products: Individual products can be selected by entering in the product name in the space provided. To remove a product from the discount, click the red minus button in the product list below it.
Date Start: The first day that the discount can be used.
Date End: The last day the discount can be used.
Uses per Coupon: Limits how many times the
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