MTN has NO customer service

I have been phoning MTN constantly on data that has gone missing and loaded late onto my data contract with them. It has been 4 weeks now of numerous calls to the call centre, calls that rarely if ever last a MINIMUM of 30 minutes at a time, I've been hung up on numerous times, I've been promised call backs from the supervisors or managers from MTN and still nothing. We are verging on almost 30 days later with NO satisfaction and contract breach from MTN's side. I am at this point and time feeling that I should cancel all 3 of my contracts from MTN and moving to another service provider. I am over the way that MTN treats their paying customers that has even through cobid and minimum salaries still kept on paying for a service that is not up to standard.