Extremely slow wifi connection

I have been experiencing slow wifi for months now. I've emailed (got no reply), then called in to get assistance and everytime I get told to unplug the router and the black box which I have done, but nothing works. The wifi which is supposed to be a 4mbps line, is testing at a 1.66 download and 0.03 upload speed.

I went into their office and was told that the best they could do was log a ticket for a technician to come out the next day. Technician never came.

I'm struggling to send emails, do online assessments, back-up data, watch tv, and do basic social media.