MTN dupes people on free airtime!

When you spend a certain amount, it is promised that you will get free airtime, data time, etc. In fact, you get the message that confirms that you have received said bonus, but when looking at your balance, there is nothing there. This has happened to me countless times. Also, when using data time for sending/downloading e-mail, it gives a significant balance available. Before you know it, you have depleted your airtime with hardly any action taking place and, horror of horrors, now you have no airtime at all! What is the deal with this? Are you trying to lure people to your \freebies"so that someone somewhere can reap the benefits of naivete? """