Pathetic service by vodacom

I have taken a contract with vodacom around 13 Aug. Was told that I will b paying 449 a month for 2 huawei p smart 2021 and was then asked if I'd like to add cli to it which will be 10 rand per device so now my amount is 469. But now I'm being billed almost 509. Why are the vodacom reps not telling us that they are going to be charging extra for God knows what..... Pathetic service vodacom Phoenix plaza I'm so disappointed it's my first contract but I will never upgrade after 30 months I will move to cell c