Trash out of bundle data option

I've been a vodacom customer for years and I just recently renewed my contract. Yesterday I bought data and when I woke up it I found an messages saying that I have used out of bundle data worth R50 and R10. Like firstly I wasn't using my phone and secondly I was asleep. The only thing I did was just leave my data on. I remember back in 2019 we received an sms that from a March when your data is depleted, your internet will be stopped but it doesn't seem like the case. Other networks are not doing this because I used to use cell c before I switched and every time my data depleted, my internet is stopped unless I change the settings myself . I'm not happy with this because more than R60 of my airtime is gone that I didn't even use