Answer might be a little late, did you check that are enough free Slots on the destination Server, if not the Coins will be refunded, should happen automagically.
if so send an InGame Ticket or an mail to support@swtor.com detailing Account Name, Char Names and involved Servers.
Then there are not enough Slots inactive chars are counting too, and you need to buy the extra slots first. (Might reading you wrong too late for me)
If it was really an error on BWs side I think you could get the transfers done for the old price, especially since there was an bug with them last week.
See here: http://www.swtor.com/patchnotes/1182017/game-update-5.5.1
The default character slots per server has changed for all players:
Free to play: Now 4 characters per server (up from 2)
Preferred: Now 12 characters per server (up from 6)
Subscriber: Now 24 characters per server (up from 12)
And additional Slots have still to be bought, I think you can buy to 100 for Subs and 10 for preferred.
