items not stacking?

[DoomShine]

first off i apologize if this is a common issue many people have posted about. the issue im having is my items dont stack whether i use auto sort or manually try it, im trying to get back into the game but this is an issue i just cant get past, i have items that are stacked from when i last played a couple years ago but now they dont and if i split a stack i cant restack them. im not running any mods at all and i have uninstalled and reinstalled the game.

[gNuff!~©~gNom3™]

screenshot of the items in question?
also, worth to know that uninstalling the game doesn't actually always uninstall mods too * this would largely only matter if you were playing in custom mode tho

**also, are you referring to same "window"? or if/when transferring to/from stash and char inventory? - because auto sort does not restack in same window

[SkittishKavu1]

If the stack is way over the normal maximum (for whatever reason - i won't judge), then when you split it up they won't go back together because they're still over the max. I believe the normal stack max for everything is 1000.