Allocations depleted /no assistance

I have a vodacom contract whereby I recieve 250 minutes per month , I recieve my minutes every 1st of the new month , after receiving my latest allocation I found that by the 9th that I had depleted my minutes which in my opinion is not possible 250 minutes gone in one week etc I dully contacted the customer service line to log the complaint to which they advised me I must pay for a itemized billing , I refuse to pay for it as I have payed a complaint I have told vodacom to prove to me that I in fact depleted my minutes as it does not make any sense that I had utilized my monthly allocation of 250 minutes in the space of 9 days , it's a complaint vodacom why must I pay for you to prove to me in dealing with my complaint , I think I'll be taking up cell c s offer to buy out my contract and leave the pathetic service and excessive cost s of vodacom