Thanks to some sharp work from Econet, we spoke to a gentleman named "Parshon" whom we put in touch with the complainant. The matter has been solved, there was a leakage of airtime.
The Econet guys got in touch and they had this to say:
"Our sincere apologies for the experience you have had on our network over the past 24hours. We have investigated the issue you raised about airtime disappearing on your mobile number. We have established that you are subscribed for a Sports News service, which charges $0.10 per SMS you receive. Kindly advise whether you have been receiving the Sports News from the shortcode 33334."
I then informed them that I had never subscribed to any of their short code services. I then got a call from the guys at CyberCard Customer Service and they confirmed that they'd received my complaint from Econet and they had found out that there was some "error" of some sort, "syntax" if I remember well. So yah it somehow resulted in my number "appearing" under the subscribed list I guess.
So the guy apologized, asked if I was cool with a refund of the lost airtime. I was then refunded with a $1 and the Cybercard guy called to confirm if I had received my refund, apologized again and then asked if everything was now ok so that they can clear the complaint with Econet. That was all.