Refunds

I want my refund, your contract states that a 20 days (Working days) notice is required for cancellation, why then do you bill for the entire month from the date of notice? How is it possible the 20 days from the 13 January 2015 to the 28 February 2015 is 20 working days. Please advise how that is calculated as I tried and cannot get to the answer. Also the network access was charged in December 2014, the agent advise the accounts department will contact me and to date I am still waiting.<br> <br> Is this a common practice for ADT to make promises but not follow it through as it surely seems that it is?<br> <br>