MTN Data Usage!

I have a data contract with MTN for the past 3 years now with no issues. This morning at about 10:30 I got an SMS notification to say my 30GB Monthly data has depleted, this came as a shock to me because I was last topped up on the 22/05/2022 there's no ways I could have finished 30GB by the 10/06/2022, this has never happened for the past 3 years, its unusual, on average I'll use just over a Gig a day on a busy day 2GBs, I also have wifi at home so I'm not always using the data SIM. I then call the customer care line requesting some sort of usage bill, mind you I spoke to 5 different consultants because the MTN NETWORK IS HORRILE! and I kept getting cut off, even after I've asked them to call me back due to the network no-one called me back. I spend and hour and a half on the phone, and still haven't gotten any help, instead I was sent a usage bill ranging from 22/04/2022 to 21/05/2022 and I was told zoom and and unknown app used up most of my data, when I ask how much data was used and what this unknown app is I wasn't given an answer. I'm so frustrated I've asked to speck to the manager and I was told they would call me back (I'm still waiting) I've had to cancel my Teams meeting because NO Data and No answers. Once again my call was cut short because the MTN Line was horrible and the customer care again don't care enough to call me back.

I need answers! Regards, A frustrated Client