"My Vodacom" app deception

I used the "My Vodacom" to by Anytime data and after my selection another question appeared on the screen asking "Do you want to also consider the following:" which were offers on WhatsApp data bundles. I chose one to add to my original purchase only to find that the app ignored my original Anytime data selection and doubled-up on the WA bundle. I contacted the Vodacom customer care and the long and the short is I must apparently first complete the Anytime data transaction (ignore the WA-bundle offer !!) and then come back afterwards to purchase a WA-bundle if needed. Needless to say they refused to change the extra 1G WA bundle to Anytime data..