We can't see your bills on here but I can tell you the discount is only on the airtime portion of your bill.
If you check in your MyO2 you should see a bolt on for the discount if it's been added.
Discount help guide here to check the process you followed
https://community.o2.co.uk/t5/Other-Products-and-Services/O2-Open-amp-Friends-and-Family-discounts-H...
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