No help at all for my disappeared airtime

Sometime last week I topped up with 100, of which I normally buy daily data bundles, ran outta my daily bundle and bought the hourly bundle of which I was left with something like 67. 10 min later after purchasing my hourly bundle I was left with R10, and then I called Vodacom to ask what happened they couldn't answer me, and said they will raise a service request, I waited for a week and didn't get any feedback from them. I called yesterday and was told a service request wasn't raised and they will do and send me a reference. I waited, called again this morning and told they can't help my airtime was used. If you guys check my top up history and what I use my data for, there's no way I can use 50mb in 7min.. All I want is my airtime back. Am unhappy about this.