Beyond level 30 I heard, however you can get books like the green book that resets every skill and brown books that takes one SP back so you can use it on something else. I also heard you can get 60,000,000 zeni and use that to reset, but I'm not sure. But if you're a beginner, then don't worry as long as you're under 30 you can reset all you want until you reach level 31 without requiring to use a green book or brown book.
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