Cell c try to rip me off

Hello Peter I've got a call from the Cell C agent selling one of there data of 5 gig day and five gig night data for R140.00 ,I've received a package from the courier company and received two data cards , I've phoned Cell c immediately telling them that I did not order what they've delivered the lady assured me that they will rectified the problem, at the end of the month they debit my account for R800.47 pls I'm so disappointed with there service and would like Cell C to fix the problem cause I didn't ask or ordered any of the products what they delivered . I've phoned them twice afterwards and was told that they will fix the problem ,but nothing has been done .I will never again in future do business with the. Or recommend there services to anyone I'm so disappointed with there services please help.