Poor service delivery!

Network very unstable, been struggling for two weeks now. Calling every day, trying to resolve everything over the phone. When I then tell them there is a problem, they say they will send someone, but they will bill me if nothing is wrong. Why would I call x6 times a day if nothing was wrong? And why make those statements?? Did speed test, running at 0.68mbps, but the guy says i am on 5gb download already. Everything I say they argue. We have three accounts from different houses, and all three houses complain. Is there no alternative?? I am fed up. When they bill you they want their money asap, but I when through 6gb data just because of there poor service, wonder what now? I am tired of poor client service.