Data bundle contract *******

I took out a contract for a data package to be used by my daughter at varsity. the package was for 5 gigs of data for R304.00 per month. Because it was for my daughter i specifically asked that it be capped, however the contract stated that there was a usage limit of R999 999.99 and i unfortunately signed without picking it up. one month into the contract my daughters laptop did a series of updates overnight and this resulted in excessive data usage of +-9gigs over a few hours. I received a bill for nearly R10 000.00 for this, meaning that i was charged roughly R1380.00 per gig. I queried this with altech and they merely forwarded a dispute for the use of the data, not for the fact that the data was charged at such a ridiculous amount, or that the contract was not capped as i requested. Who takes out a contract and agrees to pay R1m for excess charges? Altech have just said that the data was used and as such the amount is due! i am more than willing to pay for this mistake, but to be charged more than 200% more for data is surely *******!!!!