Poor Service from WebAfrica

I have been with WebAfrica since August Last year and took up the new Fibre with them I took up the 100MBs download and 20MBs upload. All was great as I did not need their after sales support until the middle of March 2018 when I could not get more than 10MBs download speed. I logged a ticket and then the poor service started. First I was told that I must reset my Router and Fibre router, which I did. That did not solve the issue. Then we had telephone support after 2 hours still nothing, then there was backwards and forwards between me and the support at WebAfrica. Then they got hold of Vumatel to report an issue and the feedback was that the line is congested. Still, the problem was not fixed. Until today the 1st May, the issue has not been resolved. WebAfrica has the cheek to invoice me for the full amount for a service they are not providing. Please be aware that the Service I have received from WebAfrica is terrible with no sight of the issue been resolved after 1 month and the Management of WebAfrica don't care as I asked to be put in touch with the Sales and Customer Service Manager and the reply was "We do not provide their details and you cannot talk to them but they are aware of your issue" Brilliant.