Airtime issue

I recharged with R12 and my airtime dissappeared within seconds, when I called I was told that it was exhausted by data, after recharging I opened a website , when I tried to proceed to access a link on the website, I then got a cell c page saying I'm out of funds, i then checked my balance and it was 0.I don't understand how opening a page could have exhausted R12 at once in a few seconds, I've recharged before and accessed internet but it has never exhausted that quickly, in fact I recharged again a few minutes later and it did mot dissappear. On the 1st recharge I didn't even have the chance to buy data, I didnt even get an sms saying one of my data bundles has depleted and what is even more strange, cell c always delays to update balance, even when your airtime is exhausted, it will still show u a balance but this time it ypdated immediately and everything was 0.The consultant I spoke to couldn't tell me what exactly on the internet exhausted my airtime, I asked for their billing per second, surely it can't be R12/sec, but he couldn't tell me.All he said was I need to restrict my background data, all my background data is always restricted and I need another valid reason of what happened to my R12.R12 may be nothing to Cell c but it is a lot of money to me, no one gives me R12, I work for that and I deserve to be given all details on what happens with my money otherwise this is *******, the sms that cell c sent me after closing this case is just not relevant to this, actually its a generic message that is sent to everyone.If it was an issue on my side, please explain to me how and why yesterday of all years I've been with cell c.