I'm still being billed for a cancelled account

Hi,<br> <br> I went to the Telkom store in Menlyn to cancel my phone line on the 25th of January 2015. I was informed that there is a 30 day notice period.<br> <br> However, I am still receiving bills for services in March which is after of the 30 day period.<br> <br> I also tried to phone the call centre to cancel my account, however, after holding on for 40 minutes I gave up.