If I could give RSAWeb 0 stars I would. Terrible internet service providers!!!!!

This is the worst service providers EVER!!! The service (if you can call it service) is absolutely SHOCKING!!! Ive been a client for almost 3years (dont ask me how I managed to stay this long) and Im now FED UP!!! We have constant connection issues. We are only 2 people in our house. We have a Smart Tv and stream everything on there. The router is connected via a LAN cable to the tv. When watching something and Im on my phone or my partner on hers the stream lags! You cant even whatsapp!! And this is supposed to be a 20mbps line. Last week I emailed them and said that after numerous calls to the call centres and still struggling with this stupid internet they need to send out a technician or representative to come and see what the issue is. I gave them a deadline and said that if no-one attends to this by Friday close of business I will cancel. Friday afternoon after 4 they tried to call me (I was driving at the time and misses the call). When I got home I saw an email from them saying that I first need to get helped via the telephonic tech support. I emailes them back and said that we've been through that already and still having the same issues. I again stated in my mail that I want a technician or Ill cancel! Sinesipo Kalimashe (the consultants name) chose to ignore my email and instruction! Friday evening I sent an email asking for the correct email adress to send my cancellation letter (no reply). This morning I sent another email asking for the email adress. Just now I received an email asking if I used the 1 hour free onsite before. Im so sick of this **** internet and lack of customer service.