This happened to me in a game today, I had 8 curses and the token wouldn't unlock. One of the curses I had stopped you from activating your weapon ability, but you discard this after gaining max health (Can't remember the name of the curse, maybe 'Doubt'). I thought that maybe it was interfering with the token unlock as it affected the weapon.

I managed to get rid of this curse and i still had 7, the token then unlocked when I collected a blessing. This happened at the same time as getting rid of the curse, so not sure which one caused the token to finally unlock.

I would suggest trying to acquire a blessing once you have 7 curses, and making sure you don't have the curse that affects the weapon (Doubt?).

Good luck.