Terrible sales service - no response from sales department

I administer my parents ADSL account and am trying to upgrade the line from 2MBPS to 4 MBPS. I have logged 2 call backs, had a very useless live chat with someone who just quoted the standard stuff about contacting sales and also spent about an hour on the line in a queue waiting for sales to answer. No resolution at all. This is not acceptable and it seems that they do not care about either getting new customers or helping existing customers