Out of bundle Data usage

<p>I have a vodacom contract - for about 10 years now - but my latest contract has 700 anytime minutes, 2GB data and limitless sms' - I have been using my data the same for the last year. I have used it on my phone and via Hotspot to my PC. None the less the last two months (without doing anything out of the ordinary) I have incurred an amount of R1500 - R2500 data usage a month. In May 2017 I purchased extra Data as I received sms' notifying me that I have alomost exceeded my data - I purchased same before completely depleting my data. but I still received a "out of bundle data usage" of R2500.35 and after calling the call centre I reset my cellphone data counter to zero, I in June 2017 received a bill of R1567.14 "out of data usage" bill. I however have left on my account - after my debit order, according to my app and my detailed balance - 11.74GB data "once-off balance data" and 2.33GB "recurring balance data". My invoice shows my data purchases of 30GB and my cellphone shows data usage of 23GB. So how is it possible that I used "out of data rates DATA" ????? as I still have data left and I purchased data everytime I received an sms that my data is ALMOST depleted. everytime i buy data I first check what my balace is and NOT one time was my data finished. I did not take screenshots of this unfortunately. I took screenshots of the data usage on my phone since 11 May (which is less than my invoice). BUT I did note that when buying data on a contract (as an extra data bundle) Vodacom does not show the date NOR do they send you an sms confirmation of the Data bought. So if you do not screenshot your purchases (as I am currently doing) - you have NO proof that your have bought data. When you call to log a complaint - you are informed that a complaint is logged at the "back" / "head" office - but since May 2017 when my first complaint was logged - I have NOT received a response. This is unacceptable and very dissappointing - I am going to stop my direct deposit (which is different to a debit order and cannot be reversed easily - if at all (i am waiting) - This data malfunction is **********!!!!</p>