Vodacom - appalling sales agents and customer care

A very smooth talking sales agent asked me if I wished to up grade my contract in January. My reply was "I do not wish to pay any more than I am". She assured me that this would not be the case. I subsequently realised what she had done. I phoned customer care the next day and spoke to an agent who appeared to be most helpful. She told me she would stop the up grade and I could just pay a small monthly fee to retain my number. However, on 07 Janaury 2021, I received a courier notification that my Vodacom "parcel" was out on delivery. I refused to take delivery of it. On 08 January 2021, I received a notification from Vodacom that my order had been returned to them. Subsequently, I have tried to cancel this upgrade via Vodacom customer care with absolutely no success. Promises of returning my call and resolving the issue have not happened. This will be my last dealings with Vodacom after being a customer for 18 years. Their service is absolutely appalling!