Tournament Tokens in Hero Battles

Why can't i buy them?

- i have more than 9000 balthazar factions un-used
- my inventory is empty

When i go to the tournament guy and click 'buy tournament tokens' he says 'i can refund u with 3 tournament tokens' if i click accept nothing happens.

What am i doing wrong?

and yesterday i could buy them normally

EDIT: now i can buy them again, weird

Additional question in this topic :
What do you do with these tokens once you have them??