Adsl line problems

Hi I need to make people aware of the terrible service I’ve received and am still struggling with from Mweb I upgraded my adsl from 4meg to 8meg in December 2017, the entire January I have been calling them to say the line is not working firstly at the speed I am paying for and secondly break in connection every little while, their excuse is always something to do with telkom faults etc, then the new story was I am overusing my internet and voila my line gets throttled! Mweb on Facebook advises to downgrade back to 4meg owhich gets done only to have this line throttled as well, no credit is given for days when adsl doesn’t work and instead money taken from my account is more than what was supposed to have been deducted... again they log a query and now 10 days later no response... I need help in cancellation of this line immediately as we’ll releasing my adsl back to telkom as I am not prepared to pay a cent more for this service!