I upgraded three phones in August. The result was a nightmare. MTN failed to allocate the airtime and I was overcharged in a big way. It was only on October 16 that the airtime was eventually allocated. 

I managed to get the overcharging for the October invoice sorted out through dozens of calls and eventually by speaking to the customer service manager.  

There was still a problem. The calls for the next period had been charged at out of bundle rates instead of from the available airtime. I had to wait for the invoice to become available to log a query. This eventually happened on November 21 - 14 days after the invoice close-off date. I logged the query on the same day. Three weeks later, I am still waiting for that query to be resolved. 

The December invoice became available today. A record for MTN. Once again there is a problem of overcharging - this time on an older contract. Although there were free minutes carried over going into the month and free minutes carried to the next month, I was billed for a number of calls. These calls date back to September! I have logged a query. 

I am waiting patiently for the issues to be resolved. Without the intervention of the manager the problems just drag on and on and on.