Which number did you use? I spoke with the Silver Line but got the same response as you did with other agents - they couldn't help. They suggested, though, ringing the usual 0344 4930787 number, telling me to ignore what the the prompts said, just select 1,2. It took an hour of hanging on but like you was anxious as flight cancellations had left me with a one legged holiday (out, but no inbound!). The agent I got to speak to was excellent and sorted the problem straight away. My telephone bill says that I was on the phone for 1hr, 20 mins, 28 seconds!

As C-W-S says, stick with it.