Vodacom overcharging Data without warning

I get a statement from May on my Data contract which according to me is a 2gig only and I find out I owe vodacom R4363.60 for data usage exceeding this 2gb. This charge without any warning and I am just expecting to pay . I Logged a Service request #(S3/88220/0A4C6) now I must send a letter and a copy of my id saying I give authorization for itemized billing on this data charges. My diospute is not where my data went it is : how can they slap me with this charges and just expect I must pay! no warning sms nothing!! <br> Then in June They bill me R 5011.51 on my other numeber *** also for data usage and out of bundle rates, the thing is I have proof that I kept an eye on my data bundles and kept purchasing data bundles to avoid this type of invoice. Service request ref for this nr. (S3/88220/0iiqj). I spend average of between R7000 and R9000 on my existing 7 contracts. This is unacceptable and I refuse to pay these rediculous amounts. Vodacom once done this a couple of years ago and I had to pay R20 000 one month for data charges . I will not allow trhis again.