Electronic Gift Cards are send automatically by the system, so probably something went wrong, I suggest you to contact LottoRace support for assist to re-send you the code.
Check and see if there is an update for the Facebook app in the app store. If not you may try deleting the app and then reinstalling it. If you give me more specifics as far as an error message I can further assist you.
I have found the same problem with bejewelled blitz and other FB flash games, and I have upgraded to the latest Flash Player. This only happens with Firefox -- the games work fine with Internet Explorer. You may want to use IE as the browser for these games.