Vodacom always quick to say this call is being recorded - but useless when you want a copy

I need some help to get a copy of a voice recording from Vodacom. this has been dragging for more than a month now and I still don't have a copy. this is why I need it...... We have a few data accounts with Vodacom for the staff that works for our company. The last few months we have been getting a bill for a number that is not allocated on our staff list. but this contact gets upgraded every 2 years by the person who uses it. I've asked Vodacom (Obed Mthenjane) to please send me a copy of the letterhead - Id and proof of address that one would need to upgrade a account that is on a business name. The reply I got was that they dont have anything on the system...... but they can tell me that the person upgraded the last time thru customer service call center. So I requested a copy of that recording so we can find out to whom this number belongs to so we can get the money back - that we've been paying on this account. Can someone please help me get the copy of the recording? please contact me and Ill give all the account details as required. The number in question is **********