Data not allocated

I have an Ipad mini with Vodacom ***, which i pay R305 every month and i get 1 Gig data. this month i did not receive data and it is the third time. when i called Vodacom they told me that i was not allocated data, i went to brooklyn mall to find out what happened and why i did not get my data since they took my money. i did not receive assistance as i was told by one of their employees that there is nothing they can do to assist me. i want to know why Vodacom took my money if they did not allocate me data and since there is nothing they can do, i would like to ask Vodacom to return my money back to my account and also to assist me in cancelling my contract with them because i am so tired of their bad service.