Bleeding me dry

Vodacom is bleeding me dry. I am a student, trying to work to support myself, and I keep having to buy more and more data or go without when I need it to communicate and keep me safe.

I have been struggling with this for a few weeks now, where previously 100 Mbs of data would last me a long while (I use it to check emails and watsapp) it is used up in less than a day. I just bought 100mbs 20 minutes ago and just got a message saying I have 30 mbs left. This is outrageous. The other day, vodacom sent a message saying "sorry for incorrect billing" and gave 500mbs but I could only use this over 3 days before it went away. That is not good customer service.

I am looking at other providers now, it isn't fair that I have spent so much money on something like data. Shame on you vodacom.