Hi, I've had a similar problem.
I ordered at 3pm on Sunday 24th March and at 10pm someone raised a note on my file that says;
'There's been a problem progressing your broadband order.
We'll get some more information on the problem and update this ticket with details as soon as we have them.
Order has been cancelled. Please check Install Diary and resubmit order once issue is resolved.
On ringing today (Tuesday at 4pm) they couldn't find a problem. They re-checked my MAC number and said they'd manually place the order and get back to me.
The good thing is that I am aware of it and have been able to contact them. With many companies you'd not know and be sat dumb and happy. Although it is a bit worrying.
I'm expecting the installation date to go back now and will be impressed if they meet it - next Tues 2nd April.
Pete on O2