Call Centre/Internet

It is truly shocking that for the last 3 months I have struggled to get my Internet working properly and more shocking how completely worthless the call centre is. I have tried on numerous occasions to call the call centre, holding on for 10-30 mins without anyone picking up the phone when put through to the department that deals with Internet problems. I did however succeed one day and a friendly, helpful gentleman by the name Neo helped me to reset my router etc. My Internet decides to go off whenever it wants to, even though my router is on and the wi-fi light is on with all the other lights. I AM NOW SICK AND TIRED of this constant battle between myself and the Internet and myself and the call centre. How can I pay for a product that isn't working? The worst part is that I work in retail myself and don't have time standing in your never ending lines in your stores when I am on lunch. This is ridiculous and unacceptable. I am at the stage where I want to refuse to pay and demand a full refund for the months I've paid for no to little internet and I feel it is my full right to demand PROPER service and a solution to it else I have to take it to the next level.