Mtn *****s data

Why does mtn lie about night time data whereas it uses normal data during the time slots allocated for night time data? I was shocked this morning when I got an sms notifying me that my data has been depleted. I was under the impression that I was using the night time data. I called the customer service line and I was told that when I use internet between 12am and 6am mtn will take the data that expires first. What a joke, it means when you have 1 week data and you use it at night time mtn will consume it first regardless of the time. I really regret using this network #Blackfriday