Top up contracts can not do post paid top up's stated by support.

Please provide answers as to why all of a sudden I'm not able to buy anything on my CONTRACT during the month as before. Some lady assisted me after being on the phone a few times and she gave my issue to contracts department. A day later some other call agent phoned me and told me that the option for buying data on my contract which is a TOPUP and pay on the end of the month is an error and cell c never worked that way. Why are this useless service given and lies are constantly given to clients. Now I've been sitting without data for about 2 weeks. What does CONTRACT mean in cell c and what does a TOPUP option means???? This needs to get resolved ASAP. I can set limits for out of data spending but it's yet again useless because of the fact that I got cut off when my data depleted. Why do I cell c staff try and brainwash customers with lies like this? How in the hell of this world does one feature exist and then disappears and support tells me that it could've never worked that way as cell c doesn't give topup options during the month on TOPUP contracts and it's been a fault on my previous contracts allowing me to buy data and get it deducted with my monthly payment. This is a brain dead explanation to me cause what does TOPUP mean on a contract???????????????????????????????????