Day Light *******

I've been using telkom prepaid for a while with no hassle. Lately when I recharge my data lasts less than 2 days. I bought 7G day and 7g night a week ago I think 🤔, 2 days ago i get notification that my data has run out???? I didn't get any notification liek all the other time,, I was just out of data. I used the app to do a balance inquiry. It said "Data not available" . Strange that data is not available for day time data, but night tome data was reflecting. I bought airtime to convert to data, and immediately I has internet access before converting the data????? What is happening??