If your shipping fee before applying the promo code is less than the discount, ShippingCart will not reimburse you the balance. Your shipping fee will amount to USD0.00.
For example: The shipping fee before applying the code is equal to USD15. You receive a code that entitles you to USD20 off your shipping fee. We will not reimburse you the USD5 and your shipping fee will amount to USD0.00.
What if my actual shipping fee is less than the discount indicated by the promo code?
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