Unhappy customer

I have been having issues with this company for the last year or so. I pay alot of money to have a 30mbps line but if I'm very lucky I will get 15 on a good day/night. But most of the time I get way below what I'm supposed to be getting like at this moment I'm getting 268kbs and when I try and call them I have to hang on the line for so ****** long I waste R55 airtime but they don't answer. They got a WhatsApp line when you send msg they say they got it msg and they will respond soon that soon sometimes can take up to a week or so if you are ****** lucky somethimes they don't answer you at all. Then I send emails normally get answered like two days later. Now I really wonder if I can start paying them for the service they give me divided the monies so I pay the prorate they way I get service from them. To the company you are going loose me as a customer soon and my friends also because we are gatvol of this ****