I bought the lvl 10 training manual and afterwards skipped to the lvl 60 manual.
I kept clicking the lvl 60 manual to reset my trait points, but nothing happened.
For those of you with the same ‘problem’, i just found this at the wiki: “Trait lines are split into three tiers, each of which requires the purchase of a training manual to unlock, which can only be used if the previous training manual is unlocked.”
I suppose i’ll just have to earn another gold piece to buy the lvl 40 manual…