You most certainly can book more than one seat in your name. The carrier will carry on accepting bookings for as long as your credit card is valid! They see each booking as separate.
To get a refund - you MUST take action right away. Do not wait until the day, otherwise the other seats will be a 'no show' and forfeited. Document all that you can and write to their customer services. If departure date is close then try and find a fax number, otherwise, send recorded delivery and keep copies of everything.
BOFH is correct, perseverance is the word.