Unfortunately your friend has added airtime credit, you dont need to add airtime credit to buy a goodybag, because when you do, you run the risk of it being taken, especilly if your friend has mobile data turned on, what your friend needs to do is go straight to the goodybag page by clicking OUR OFFER / SIM ONLY PLANS or by going to this link SIM only plans
Your friend can also call 43430 option 2 and listen to the goodybag or airtime credit balance.
and check exactly what has been purchased by going to MY PAYMENTS / MY ORDER HISTORY to check your latest top ups, goodybag purchases .
You could ask your friend to log into their account and ask about anything if unsure, we are always here and happy to help.
If my reply has helped you please Kudos and please Mark as Best Answer to help others!