Service please!!!

I app**** for a line extension in my study on 21 September 2015 - no new lines, only an additional jack in a room. I have subsequently spoken to 2 customer service officials (after the initial contact advising me that it is a new service and it will be addressed within 21 days) who have escalated my request and still no word - this after I was promised last week that I would receive a call by the end of the day to book a time.