Bad service

I app**** for a cellphone contract with cell c and i got approved. The debit order amount was supposed to be 499.00 a month as per our agreement and the contract but to my surprise ithey have increased the debit order amount to 509.00 but he data and minutes are still the same and I was told when I called that the debit order amount wil increase yearly. Secondly i am not getting monthly statements even after providing it to the agent and lastly, i have requested for the debit order date to be changed to the 25 but its not fixed. So far cell c i am an unhappy customer and I don't think I will continue with you guys after this contract.. also your social media consultants are rude, there is a polite way to deal or even resolve queries without being harsh, i did not like how i was answered on Twitter