limit giftcard to apply only on certain products that belongs to a specific cat.

Hi!,

I am trying to use the solution indicated here https://projectdmc.org/support/topic/how-to-limit-giftcard-to-certain-products/ but this code, applies the giftcard code and no notice is shown,also it applies the giftcode in a product that it hadn’t to be applied.

Thank you for your support.

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