Dissatisfied client

I have a been a client for more than a year. Endless hassles from debit orders being made without consent to endless slow internet always being reminded the following: "As you are on a 5mbps 1:20, you may experience buffering as it is not meant for streaming. With your contention being 1:20 you are guaranteed a minimum of 250kbps. Depending on how many of the 20 subscribers are online will determine the bandwidth that you receive. Your bandwidth will fluctuate depending on how many subscribers are online" Somedays At peak times even the minimum of 250kbps is not achieved. I have had the usual technician story all the time, have emailed the customer support in December 2019 haven't heard from them yet I further think that the wording used in their advertising of 5mbps 1:20 is misleading as it would be impossible to get to 2mbps for a consistent time