Intermitent line and bad service on top of that

ok so yesterday at 10:00 in the morning the ADSL went down. After waiting 20 min for someone to pick up I was told that they were doing maintenance on the exchange till 18:00. We have had trouble with the exchange recently so this was welcome news. <br> <br> Then today I get into work and I have intermittent service. I call the call centre and twice my calls are dropped once after 20 min and once after 30. Then I get through to someone- he does a port refresh which takes about 10 min of him struggling to get it right. so I plug my router back in and wait for it to connect. The light flashes green a few time and then turns red for a few seconds and this continues. I say to the guy that clearly there is a problem because this does not normally happen. he tells me to wait a little while to see if it fixes itself. so I do. still the same . so now he tells me that it is fine on his side and there is no problem. so I tell him I want to speak to his supervisor, so the guy puts me back to the switch board to start from scratch. I do this and the call gets dropped. I have now been waiting for someone to answer for 45 min. please help me resolve this issue.