very dissapointed and upset - Cell C Makes a fool ou of me

really disappointed with Cell C after my first complaint, they called me where we reach an agreement them giving me a credit which was half of my subscription for a mistake that was not even done by me but their *********** employer, now they only load Data for R50 on my account they think I wont see, when I request for the validation document I must wait for a month , why cant they proof now how my data was used if they have nothing to hide , There is no way I can finish 15 gig in 3 days I have been using this contract for almost a year now I have never finished my data in 3 days it last, now since I was suppose to get a credit they also took my data. I want that validation document now not month but now it my money I must be able to see how I used it