Slow speeds constantly

We stay in the Southern Suburbs. We recently upgraded to a 4 Mbps line. We have a 50 Gb Bolt on and 50 Gb monthly cap. Our speeds are constantly below 1 Mbps, and go as low as 0.1 Mbps with high pings. I have called SO many times (I have reference numbers for these calls). Every time I call, they reset the ports, ask me if I have a splitter and tell me to do a speed test. This does NOTHING. Then they say the Cape Town is having a latency problem!! I have friends whose internet speed is just fine....<br> <br> Please, we are paying for a service. Either explain what you mean by \Cape Town"is having an internet problem"