high billing

Good day i have 3 contracts by telkom which 2 is joined and 3rd on on its on now what i would like to know the two that is joined both is due for upgrade. now the one is a 10gig internet ****le what i didn't upgrade last year and im having no problems with that on but this one ( 1 x Deal SmartPlan 100 Samsung Galaxy S4 mini 8GB White) price is normally R269 now i upgraded with mobile talk the 3rd of November and still waiting for the phone. so now i phoned telkom and what the funny part is my 10gig ****le of R199.99 a month which i haven't upgraded sins last year remains the same each month but my other contract 1 x Deal Smart-plan 100 Samsung Galaxy S4 mini 8GB White price went from R269 to a R 456.50 where i upgrade to a SAMSUNG A5 with mobile talk on the 3rd November. now when i phoned telkom requarding my phone bill being so high they tell me one contract is cancelled by me where i didn't cancel my contract or contracts. and on email u send im being over billed but will be re-credited why how