airtime disappearing

My airtime dissapeared on my fone an amount of R275, I called mtn on the 5th of January and I spoke a woman called mathilda dlamini and she said my matter will be sorted in 2 to 24 hours, I called the next day I spoke some guy and I was told it takes 5 working days, I called again on thec13th spoke to a woman called Clara matshoba, she told me my matter will becsorted in 24 hours, nothing happened, I called today and demanded my airtime back, I refused to hangup until I get my air because they failed to log a call three times already, a woman called promise ntombela a team leader put me on hold for over 2 hours with no answers and im still waiting, I edge people to come forward with this issue I know 3 people already complaining about the same thing their airtime disapearing on their mtn network