Incorect Account & incorrect Billing

So Telkom had a Black Friday Special for a Huawei B315 router & Included 20GB Anytime Data + 20GB Night Surfer Data on their SmartBroadband 10GB – R199 pm (Double Data Promo) I placed the order online on the 24th of November 2017 & a consultant called me the same day to confirm all the details of the order. I was supposed to receive my router within the next week but only received it on the 8th of December. I checked the router & the sim card but it seemed as if the sim card might need to be activated or rica-ed & I decided not to use it as it was already into the month of December & I did not receive any communication from Telkom during the month of December. On the 8th of January, I receive an email from Telkom with a statement that is now charging me R270 for data usage from the 08th - 31st of December & I never used any data during that period. They are also now charging me R349 for the month of January & I am only receiving 10GB Anytime Data + 10GB Night Surfer Data. This is unacceptable from Telkom as they are now charging me R349 instead of R199 & I am only receiving 10GB instead of 20GB. Is that how they catch people by lying to them about a Big Deal & then you get half the data & charged double the amount. This entire situation needs to be rectified & don't expect me to pay for December, for Data that I did not use.