Vodacom irrational staff

Yesterday the agent by name of Viola Isaacs phones they don't check on the system my contract was for 599 and first 3 months I paid 399 which did happen but Viola Isaacs refuse to check and just enforce just like Mr Clinton October did ,they don't check they just steamroll so they rude irrespective what you say they determined and just give you the middle finger I explain they must prove I signed up for 699 she just told me what she believe so Vodacom don't listen or understand if a contract is for a year 599 then how can they change ,I asked her to send me the email where it states they can increase it ,till now nothing from her irrational people on staff at Vodacom like Clint and Viola isaacs