'continue' got overwritten and all the progress from my last day were gone

so I spent my whole day finishing off the cosmo canyon side quests and reports until I tried to fight the classified report boss and lost and chose 'restart from my last safepoint', and It restarted at the point from a day ago. all my progress were gone. I freaking yelled. lucky I didn't finish off that god damn Chocobo sliding quest yet or I will damage my tv. I know, I should manually save, lesson learned. but it shouldn't overwrite my continue save either.