Crashes on Iifa tree

Its a great game with great features, can not deny that. But, as soon as i reached the Iifa part where i had to defeat the mist monster, the games immediately crashes. I tried continuing the game nor loading a saved date, but still crashes. What is there that i can do? Im not even half way and i feel like i just wasted 21bucks... Can you please solve this. Btw, my device is an Ipad Air. I hope the device isnt the problem.

Thipkesone about FINAL FANTASY Ⅸ