Upgrade fiasco

I assisted my boss with the upgrade of his MTN contract via the MTN call centre.

The upgrade was processed on 04.12.2017 and since then it has been an uphill battle to speak to a agent. I am still trying to figure out the following;

1) Why the credit limit and usage limit was defaulted to “0” when the upgrade was done (this was never the case when did a upgrade at a MTN shop) 2) Now we are struggling to amend the usage limit and credit limit on his number 3) He received a extra sim card and I am struggling to contact the call centre (the options when I dial in is not helpful) to discuss this with someone?

Please can a MTN agent (who is actually able to give me thier direct contact number) contact us in this regard.