Not getting what I am paying for even after 5+ months of fighting!!!

Getting nothing for the mountains of money Telkom charges me every month for the 20mb/s line that I am paying for have been logging a fault with them since the end of 2017!!!!! Always get told someone will give me a call back but typical they NEVER EVER DO!!! And to top it all of apart from getting a 3mb/s line even though I am paying for a 20mb/s now they sent me my bill this month for almost DOUBLE what it should be. WORST COMPANY EVER!!!!!!!!!!