Unable to closed deceased account

I've been trying to close the account of my deceased wife but have been able to do so. I contacted customer care who promptly responded with the legal department's email address. I then contacted the legal department and they advised which documents I needed to submit. After submitting the documents the legal representative told me that I need to return the device to an address in Constantia Park. I requested to keep the device and asked for an invoice to settle the amount owing on the account including whatever would be needed to settle the phone. This was requested on the 6th of August and followed up on the 20th. I contacted the call centre on the 31st to enquire about this and the representative gave me het e-mail address, to which I sent all communication and documentation. Once again I am waiting for any type of response. Please assist me with closing this account.