I was in GMTourney I betted hamman to win with 100 tc, they drawed and i got 0 tc back

When you bet in a match and the players draw, noone will get the TC. Everyone will lose the bet. You wont get your TC back if it's a draw.

Why is that? It's really tragic, two important people, lots of bets, and it's a draw... enough said.

You betted on Tori to win, Tori didn't win, you didn't win. That's how it works.
It has been like this ever since and many complained about it, because they can't loose.
On a side note. 100 tc really isn't that much ;)

Would you like me to refund your tc? Like GerFight said 100tc isnt really that much.

Anyways, a draw will cause everyone to lose thier tc. The only way you can get your tc back is if the owner of the server (in this case the GM) were to act fast and type /cancelbets to refund everyones tc. This must be done before the next match starts or else the tc will be lost...FOREVA!!!

Usually, you wouldn't be refunded unless a GM was feeling generous about the situation at hand, but I'll pay you your TC back as you didn't seem prepared for this to happen. ;)
For future references, this is just one of the risks of betting.