Double Debit Mess Up

So a long story short, app**** for a phone, was approved and the phone was couriered. However, the courier company actually stole the phone and delivered an empty box. After fighting and complaining the handset was replaced and I collected it on 26 May 2015. I was not debited end of May and that is std practice. This morning i was debited R1088.00 for two months subscription. WRONG! I only had the handset for 5 days in May and that should be a pro-rata amount and have June in full debited. I tried calling the call centre they telling me about 7 working days and calculate that as 12hrs = 1 working day which means in two weeks I will HOPEFULLY get feedback. This needs to be investigated and I need feedback ASAP or the DO will be reversed until such a time I do get feedback!