Back in time

My save went back in time from 13 spring year 2 to 6 spring year 2.
I have copy and paste backups several times, but nothing. No Smapi error, just back in time.

It happens today so i don't know if it's Smapi, the beta update, one of my mods, or the fact i married Maru
I don't know how to solve it.
These files are from "save backup", if someone want to control them

PS: I share Steam with my sister, i have the 1.3 game, my sister the 1.2, but strangely Steam don't notice this thing...

 

@D.Grey Be careful using Steam Cloud Sync when you have multiple computers; Steam will occasionally sync the wrong version or make saves disappear entirely. You could try checking if your sister has a newer version of the save, but it's probably gone. Save Backup creates one backup per real day (not in-game day); if you want more backups, you can add Advanced Save Backup.

 

A little Update.

I have deactivated Steam Cloud for this game. Now there is a strange event. I have played a couple of days in game now and if i load the game my save is updated. But if i search in the save folder i notice that the save file are updated to the 6/20, like in the upper file i have uploaded (now i don't really know where this game take the save). Even the smapi errorlog is from 6/20/2018 so it can't help me. Save Backup and Advanced Save Backup does not work anymore.
So i have installed Smapi for developers and i have found this.

But i don't have changed the file position at all, so i don't know what is this.
Have i to ask my sister?

Sorry for my english


Update: Ok, Save Backup mod works now (strangely, It was the antivirus), but the rest stay the same. I don't understand
Update: Advanced Save Backup work only in pre-play saves