I'm sure everyone here has experienced mileage for hotel stays failing to be credited to their EC account. What is the most frequent cause of this? The causes I can think of are:

- Hotel staff not properly registering EC number on booking.
- Hotel not sending mileage credit request to hotel's head office.
- Hotel chain head office failing to process mileage.
- BA failing to credit mileage received to EC account.

I've recently started e-mailing hotels when mileage credits fail instead of faxing the hotel bill to BA. This seems to produce quick results.