Does people know that Telkom mobile deducts from your night shift data and in the same time also takes from your day data

Does people know that Telkom mobile deducts from your night shift data and in the same time also takes from your day data. As soon as it goes over to midnight. Nightshift data kicks in. But then your day data also gets deducted. The client centre told me that i should put it on airplane mode. But it does not work. How is this possible. And also when there is no day data, you cant use your night shift data.