How can i finish 50gb of day time data within 2 weeks and its the 3rd month now

I have a home wifi contract with MTN i pay R269 for 120 gb the 50gb day time data lasts 2 weeks and it is the 3rd month its happening i have been calling their call centre, reporting on this on their fb page but no help again this morning it says data depleted and i am the only one who uses this data i have had enough. I cannot finish 50gb of data all by myself within 2 weeks never. MTN stop ripping me off this is the 3rd month it is happening.