Taking data and over charging

On Friday 29 January over 700MB data and R35.00 airtime was taken off my phone...... MTN accused me of airtime and data being depleted because I downloaded a video. My phone statistics shows no video download and the customer care or the branch can't tell me what video and what time this video downloaded. <br> Still can't believe this<br> Further more after spending 4 hours at the branch needing answers and technical MTN provider looked at my phone to see where the problem might be and what is switched on that can possibly take my airtime and data, NO LUCK<br> I bought 1G data, 2 hours later after leaving the store, phone not once used 400MB was gone/used.<br> I can't explain it and neither can MTN, they can't even prove their accusations, that is how bad it is