Worst customer service award winner VODACOM

I was offered a laptop deal from Vodacom. I accepted the deal. Before delivery I was offered another deal on a laptop by vodacom which was better than the first deal. They delivered the first laptop which I returned. They delivered the second laptop which I also returned because it was not what I had been offered. See both credit numbers and courier waybill numbers. o/n ***, waybill K*** and o/n ***, K***. This was nearly 18 months ago. When I checked my last statement received early november I noticed something amiss. (I am being billed for for something returned nearly 18 months ago). When I phoned to enquire I was given a total runaround. I went into the vodacom shop 921/11/20) at Baywest shopping centre in Port Elizabeth to try and get some assistance. They phoned customer services and eventually were told that a supervisor would phone me back while I waited in the store. I am still waiting for that phone call. I went back to the vodacom shop (24/11/20) to try and get assistance again. I was unsuccessful and it is impossible to speak to a manager. The credit I should be receiving is over R4000.00. I received a call from a gent Andrew who said he would sort out the problems and would phone me on friday 27/11/20. Needless to say this never happened. Now today 2/12/20 My debit order went through and instead of my normal debit order for about R1600.00 going through and receivng my credit I have been debited with R5786.00 putting my account past its credit limit which has never happened before. Again I tried to phone and after being on the line with no success for over 22 minutes I was cut off. The staff in Vodacoms billing department are totally ***********.