MTN Cutting calls?

I've not been able to get through to the call center at all today.<br> Please assist with an ongoing issue (Number below). Since returning from overseas last week, I've been having this issue where people phone me, only to have the phone ring once and then cut. On my side the phone does not even ring and I only get a missed call. This is not acceptable as people think I'm being rude, killing the call.<br> <br> Please assist urgently with this ussue