Weird glitch in my BBS game, wondering if there's any way to fix it

So, I recently went back to the MF fight just for the heck of it, but every attack he hits me with, regardless of the character used, bypasses both Second Chance and Once More for a one-hit KO. Now, all my characters are lv. 99 with all stats maxed out, and I only have the game on beginner mode, so there's no way he should be one-hit KOing me, and even on Critical, Second Chance and Once More should prevent one-hit KOs. Is there any way to bypass this glitch? BTW, I'm not running CFW, nor do I have AR installed on my PSP.