Do the telephone booking people have a clue?

I went online this morning to check out prices for a trip to Germany next May half term.  I went through the booking process and got my price but found that extras needed to be booked through the telephone booking service.

So I called a little while ago and spoke to Erica who said that she couldn't help me because the P&O crossings on that route hadn't yet been released.  I explained that I had got a quote on the internet but she said that even though they might be on there, if I got to the end of the booking process it wouldn't accept my payment because they definitely haven't got those crossings to sell.

So I went back online and went through the booking process, paid my deposit and, hey presto, I am now the owner of 4 tickets from Hull to Rotterdam with a Caravan Club confirmation to prove it.

Explanations anyone?