Incorrect billing for the 2nd month

Good day,<br> <br> I would like to complain about MTN SP service as it seems like they have billed me again incorrectly for the second month according to the email confimation that was send to me on the 7 April 2015 a credit would have been processed towards my account for March for incorrect data bundle charge. My cell number have been out of contract since the 31 March 2015 but to my suprise I was incorrectly charged for the hardware device fee which should have stopped billing on my March invoice as all subs are paid in advance.<br> <br> I have requested an confirmation of the credit that are due to my but have not received any feedback yet. Seems like we as consumers must keep an eye on our billing from MTN as this is the second time since I have my contract that I was incorrectly billed.<br> <br> I hope that this matter can be attended to speedly as this is unacceptable that we as customers need to follow up on credits that are due to us.<br> <br>