Billing not showing half price broadband

[#1]

Hi
When I ordered my unlimited fibreoptic broadband package in Jan 2013 it was advertised at £9.99 a month for the first 6 months followed by £19.99 for the remaining 12 months of the 18 month term.
When I called to provide my MAC code I queried this as it was showing up at a charge of £19.99 a month in my account details. The gent I spoke to said "I knew you were going to say that, dont worry its an administration technicality and you will definately get it at £9.99 a month for the first 6 months"
My first payment on 29.01.13 included 12 months line rental up front AND a£19.99 ADSL initial subscription charge. My fibroptic broadband was activated on 11/02/13
My first routine bill has arrived today and surprise surprise I have been charged the full £19.99 again.
This means that instead of paying £9.99 A MONTH I have been charged  £39.98 for 1 months fibreoptic usage from 11/02/13 - 11/03/13!!!!!!
I have opened up a ticket but would appreciate this being sorted out asap as its not a good introduction to your company. In additional it is against the law to advertise a product at one price and once the customer has signed up charge them a different price! I look forward to this being corrected very quickly to prevent the need of taking further advice from trading standards.

[#2]

Hi JulieE,
Firstly welcome to our community forums.
Sorry to see that your discounts were not applied, I have now added the discounts to your account and they will run for the next 6 months. You've paid the inital fee which is for the first months broadband 11/02 - 10/03 and your most recent bill which is for the dates 11/03 - 10/04.
I hope this is OK for you?
I've updated your ticket too.
Chris

[#3]

Hi Chris
Thank you for applying the discounts. I will check the bill on the 11th April and monitor that the discount is applied for the next 6 bills. Thanks again for your quick resolution.