Not Receiving Calls on Telkom Mobile Contract

I have gradually stopped being able to receive calls from ANY MTN numbers and some other numbers (including Vodacom)<br> <br> I reported this issue on 13-02-2015 (Case no: ***8) and was told I would receive feedback within 3 days! I have heard nothing further and the problem is still there. I initially thought that the issue was limited to MTN numbers but have since had complaints from other networks. I cannot receive or send SMS to these numbers either! <br> <br> If they cannot provide the VERY basic service of receiving calls, then they must release me from my contract! I ported from MTN / Autopage at the end of last year because of dropped calls, and now I can't receive calls! I am losing business and this is completely unacceptable!