Saves in game

So basically I have been playing pokemon insurgency for the first time and it has consumed my last week or two. I had 40 hours and mons around level 70. Today me and a mate decided to do a duo nuzlocke and because I had read online about different save files I mistakenly overwrote my I’ll save and we played for a few hours saving regularly. I would really like this old save to be back playable as I was very invested. If anyone more tech savvy than me can help please please do.

I dont think that’s possible, if you saved multiple times, it would have overwrote the backups. Did you change to save file 2 before starting a new game, or not?