Here's some ideas, and these are just opinions so don't be discouraged:
-Maybe they're not interested in the prizes, be it they already have them or just arent wanting them
-You posted it late at night, and the forums tend to be more active during the afternoon/evening hours (in america, that is)
-Busy forum
Also, your second entry was a hefty amount of tickets so people may be intimidated or feel they may not have a chance Maybe advertise it somewhere! If you're in an ACNL discord you can ask a mod to show it there, or if you're in any facebook groups you can link it there, etc
I personally don't like raffles where I have to spend TBT for entries. I'm cheap and like giveaways where I can enter for free. Not sure if other people think the same way or not. Just giving my opinion. XP