The codes are only applicable to the Home Health website. Here they are just to check you have them correctly:
5 packs 264086
10 packs 975833
Once you’ve clicked on view basket, scroll down and you’ll see this box, circled in red. Insert the code there.
So far as I recall the code only gives the discount on the home-health website.
Go there select the strips and amount you want. Add to basket.
Then go to "Cart" and copy the coupon code into the box.
Then hit apply coupon
You should then see the coupon discount applied in the total box