I keep complaining that statements sent to me by metrofibre indicate old address

I keep complaining that statements sent to me by metrofibre indicate old address. I sold the place and moved out in July 2023. To date metrofibre has not changed address on statements even though I completed change of address form in July since I moved to the new place 26 July 2023. I gave phoned metrofibre and told matter will be escalated to finance. When that did not happen after a number of follow ups still nothing. I emailed metrofibre still the statements show old address please escalate to the person willing to assist it's now December my statements show address I soks. Why?