Data bundle depletion issues

Telkom offers reasonable value for money but what seriously annoying me is the fact that I bought a data bundle towards the end of April. According to ICASA Telecoms companies should always use the oldest bundles first before new bundles are used up. I see my newest bundles are used and my oldest are not being used since I got my new data allowance on 01/05. Please TELKOM call me and explain why my oldest data bundle is not used. It I don't get a call I will call ICASA next week and lodge a official complaint and start whatever process I can to get you guys to respond. I see this as dishonest business behavior.