Charged twice for a cancelled trip.

I requested an UBER cab at fourways mall and the assigned driver ( sibusiso) and waited for him to come. 15 minus later I received an sms indicating that the driver had cancelled. I tried to call the help desk through the UBER app but failed. I tried to call the driver but failed. Then I received an sms indicating that I should cancel the trip and request another one. I did not cancel the trip but tried to reach the help desk. Then I was charged twice for the cancellation. I'm still surprised by this as I really needed the can and was left inconvenienced and charged twice.