In order for the BOGO to apply you have to add 4 eligible (from Make Your Own Kilo Category) 250g bags to your cart. You will get the discount at checkout (one free for every 3 you buy).

You must add 4 bags to your bag/cart to receive the discount of buying 3 getting 1 free. (All 4, even the free one must be added to your bag/cart).