Speed issue does not get solved!

This has been going on now since beginning of July. I changed from Octotel to Openserve and is supposed to get 25 Mbps line speed. Only had that speed once in a while, this morning speed is 6.8 Mbps. Every time I log a ticket with home-connect, somebody else phones and we start from scratch, changing channels, problem STILL not solved!! Why is it so difficult to sort out??