Poor service from Cell C and Courier It

On 27th Nov, I upgraded my contract. I also updated my Residential address and informed the agent that it was different from my postal address. On Mon 30 Nov, I received a call from the courier company Courier IT to inform me that the delivery guy was at reception with my delivery. I proceeded with my ID smart Card and Proof of address. However due to the address on the invoice reflecting my residential address instead of my postal address, I was told that they would have to take the parcel away and deliver at a later stage. I came back to the office and I called cell c and changed my information a second time. At approximately 09:45 on 1st Dec I contacted the delivery company and I was informed by an agent that I would need to call cell c and request them to send an email informing the courier company that my details have been amended. After I ended that call I called cell c, of which I waited on the like for more than 30 minutes. I was assisted and the email was sent. I followed up by calling the courier company to inform them that the email was sent, however I was advised that the parcel was dispatched back to the address of the sender. I then called cell c for the second time and they informed me that they cannot do anything because the parcel still reflects on their system as with the courier. According to the courier company, it has been received by cell c. I have made several calls and queries trying to rectify the situation and have found no joy.