Problem with voucher codes validation

[ftardio]

Hi!

I'm having some problems in my prestashop e-commerce with application of voucher codes (PS 1.6.1.17).

If I have a voucher code for some time limited discount in my shop, for example, active only for a week, I notice some customers are using this code (and they are having the discount in their orders), AFTER the code application has expired and it is inactive in my PS back-end panel.

I have seen the discount is added to the cart like one more product, and its validity is checked when you add the code at the cart. But if you don't finish the order at that moment, and you return after some days and your cart is still active, the validity of the code isn't checked any more, so if you confirm then your order THE DISCOUNT IS APPLIED, EVEN IF THE CODE IS INACTIVE at the moment you're confirming your order.

Is this the regular behavior of PS or I'm having some problem in my shop? How can I prevent it and fix this problem?

PS: I'm using the "one page checkout" form for checkout (I don't know if this relates the problem).

Updated: If you add new products to your cart once the voucher code is applied, the validity of the code is checked again, and if inactive, it desappears from the cart. But if you don't add any new product and you simply confirm and order your old cart contents, the code is not re-checked again.

Edited January 10, 2018 by ftardio (see edit history)