Please be better

Hello there, Today I am complaining because of service delivery, I pay R505 per month to have a ADSL line at my house, this line is a 4Mb\s line, or so they say. If I run a speed test the line speed varies from 1.5Mb\s to 3.8 Mb\s for download speed and for the Upload speed it is about 0.18Mb\s. I just want to know, how can I be charged for a 4Mb\s line but never reach that speed. According to me, If you pay for something and you do not get what it is advertised for, it is *******? I try to send E-Mails, but if the E-Mail is bigger then 1MB, it gets sent 80 times or more because the E-mail client times out because of the slow upload speed. Why do we need to take this? Why do we need to accept that we pay for something that does not live up to what is said? Why do I even have to pay for a land line rental if I do not want it? Just for me to have a ADSL line I need to pay R200 more to rent a land line and I don't want it, I have a cell phone, please explain this to me, Its 2016, not 1980, can't you find a solution to actually satisfy your customers needs and not overcharge them for stuff they don't want and actually give them what they are paying for?