No contact details for overseas clients

In February 2022 I moved to the UK and went to Vodacom regarding my sons contract. I was informed that contract would expire in December 2022. As my son was going to be between UK and SA, I decided to keep it until then. In November 2022 I contacted Vodacom to not renew contract from December. I was told to email early cancellations, which I did and explained the situation. No response! I emailed in December, January, February to customer services and early cancellations and no response yet debit still going off. I reversed debit in February. I am not getting emails from Vodacom saying I am going to get a negative record on my ITC if I don't pay. Of course they send email from a 'No Reply' address so no other way to get hold of them except phoning them. My father, who has Power of Attorney was told he can't do anything when he went into a branch. Vodacom threaten but don't listen. Over them and their bullying!