Cell C fibre TERRIBLE

I have recently installed fibre from Cell C, or called C fibre. I took a 100/25 mbps fibre line package from them. Since the day it was installed i have had problems. Not only is my speeds all over the place, half of my games i cant even play for some apparent reason they cannot tell me. I still have my telkom adsl line, and when i plug that in everything works fine, but as soon as i plug in the fibre from cell c everything is haywire, games cant connect, tracerts are timing out u name it. My speeds is ridiculous, 90% of the time i get 5mbps if im lucky. I have phoned their customer support and logged tickets SO MANY times and im out of options now. They just CANNOT give me a reason why my line is so bad. The latest one was that octotel has issues in my area, So i phoned octotel myself and they responded that there is no issues in the area. Its been almost 3 weeks now since installation and still no result. Not even a technician to come and check my line. NOTHING. Best of all is i now have cancelled my adsl line and am forced to sit with this and no one can help me. RIDICULOUS!!!!