Yes, it’s a code that you use on the Amazon UK website.
You go in, choose the relevant Stick (Lite, the cheapest, most basic one), put it in your basket, and go to Checkout. There, under 2. Payment Method, you can give the supplied code in the Add a gift card or promotion code or voucher box, and choose Apply.
This should drop the Order Total from £19.99 to zero.
The promotion does expire, but not until 2nd November, so it shouldn’t be that.
Have you done the above?
If so, where did the process fail, and how?
I suppose it’s not possible that somebody already used your code, somehow?
NB: It’s a shame you haven’t used the voucher as early as I did, as I saved £29.99 there 😛
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