Home router cancelation

Last week I got a call from mtn , sales lady I can't recall her name , sold a Home router to me , she said I have loyalty points since I've been with mtn so many years, she told me I will be paying R99 for 36 moths for uncapped data , asked why it's so cheap , she said it's because of loyalty points, I asked her about 3 times , she confirmed it was R99 , so I took the contract , mind you I have 2 contracts already with mtn, so anyway I went to mtn to check my bill , they told me my bill is R399 , so basically this lady **** to me , I'm so disgusted by this , that she will actually lie to me in order to make a sale, she **** to me, so I don't want this contract please cancel , I've been sending emails , calling no one is willing to help me , I've been with mtn for 10 years now I'm a loyal customer, I don't deserve this treatment, I want this this contract router canceled with immediate effect , and I will not pay any cent towards cancelation, the person to sold this to me must pay not me , I'm disappointed with service from mtn , please organize collection for this router, I don't need it