How to communicate with Pipex?

I signed up to a retention package that included "Anytime International"
phone calls. There are two problems:

1. On the Pipex site the call costs are not listed for Anytime
International.
(They are listed for both Hometime and Anytime.)

2. On the "My Pipex" site I cannot view the phone calls I have made.

I have rung them three times about this, and each time they have said
that the problem would be fixed within 48 hours. The last time they
said they would send my call details by email. Nothing has happened.

Is there a way to communicate effectively?
Would snailmail be better?
Is it a good idea to copy a letter to Oftel?
Any hints and tips?

I am not intending to moan; simply to find out how to make something
happen.
All practical suggestions will be much appreciated.
--
Chris

Check out the forums over at thinkbroadband.com - I posted the Chief
Exec and Chairmans' email addresses a while ago (might have put them
on here as well a couple of months ago)