Billing Department - Billed for cancelled line

I canceled my Telkom line and all services were suspended on 23 Feb 2018. I sent emails to ********** since 7 March 2018 and have not had any joy. Please refer to my email sent below and assist.

Dear Telkom Billing

Please check your system and my invoice. My services were canceled on 23 Feb 2018. I am only due for the phone calls made, not internet as indicated on your invoice.

Please urgently assist with the correct amount that I need to pay to settle my balance with Telkom. I do not have services from Telkom since 23 Feb 2018. I have unplugged the modem and telephone, so there should not be anything on it.