I bought airtime and mtn didn't credit my account

<p>I bought airtime on thursday on cellphone banking . I got confirmation from my bank that my airtime was processed n the money was taken from my account. However I didn't get an sms from mtn saying my account has been topped up with 50, I then called them to ask what's happening they said they were experiencing network problems and that my airtime would appear around 7. That was around six on Thursday when I called. I have been waiting for my airtime ever since and when I call them they keep on saying that my airtime will be credited to my account but that never happens. I want my airtime today or I'll cancel your **** contract. </p>