Pathetic internet speeds instead of 5G

This my third time i am paying rain over a R1000 for 5G unlimited internet i am getting speeds of 0.45mbps down 2mbps upload that is far from 5g i actually have complained a few times with them i call their call center you get people seems they are working in a farm cause all you hear is chickens they are over charging me for pathetic service i have a old modem they promised to exchange the older for months not one of them came to fix this i have been loyal customer to this company for year even if they overcharged me but this is a step to far they have refund for the service i am not getting and if my service is not improved i am cancelling