Retentions department non-response

No response from Retentions to cancel my phone. I am living abroad. Have a now not used MTN phone, not in contract. Want to cancel. Cannot call the 08 number from abroad and email to Retentions just go answered no matter that I now send emails daily. Yet you continue taking money every month from my account. Does anyone work at Retentions or is it just a dummy account? The next step is to just cancel my debit order and wait for you to try sue me.