Unable to update address

I have been trying to get Vodacom to change my address on my statement since June. I have not lived at the address on my current statement in over 5 years.

And it just seems to prove impossible. After various phone calls, it is still the old address.

Shocking how they are quick to pop you a sales call (after which the sales consultant did not send me anything that I asked her for), but when you need real support, it's just not there.