I was able to successfully install and play zenless zone zero through steam. I installed the game launcher onto my OS drive but the game itself to a seperate Linux drive. I was able to play and install updates for a long time until yesterday. There was a new update out I tried to install it but it said I didn't have enough space. I have 300gigs available on the drive its installed to so I thought for some reason it's trying to install it to the OS drive. I wasn't sure how to fix that so I figured I'd just uninstall it and reinstall it to my second drive. But now when I go to install it, it says my drive doesnt have enough space. I'm not sure why it would say that when I have 300 gigs available. I also tried re installing the launcher onto the drive that I want to install the game on, but it won't install to a drive that isn't C: not sure what I can do now.
EDIT: I tried every solution suggested below, nothing worked. I eventually gave up and connected an external drive that's NTFS and the game installed to that. Thanks everyone for the suggestions.
EDIT 2: after thinking about this I remembered that when I first installed ZZZ, I didn't have my drive auto-mounting on boot. I guess after making that change the launcher didn't like my drive or something
Is your drive where you install games automatically mounted by the system? In case something changed in your system, does it have the same path as Steam expects it to? And is the drive a separated storage? And though it may sound like a stupid question, I think it's important to ask also, are you sure it's on the storage you think it is?