Telkom are *******

I am battling to have an account and balance removed from my name with Telkom. They delivered an LTE product to my address. I was not there to collect. Yet the package stated only the owner can accept it. First breach of Telkom. I never opened the package nor used the service. After several times sending in a cancellation form. I am now getting calls from a collection department. I already returned the package. Yet the balance is still linked to my name. I want it removed as it is messing up my Credit Score.