external hdd disapeared

I have a hdd attached to my server. It's sda but has 2 partitions so sda1 @16M and sda2 @3.6T It defaulted to being in the location /media/devmon so I kept that and it worked for ages. Suddenly the data is gone. I had files located here: /media/devmon/4tb_drive/kiwix/zim and that directory is now empty. But I put the drive into a Windows box, and everything was there.

When I run mount /dev/sda2 /media/devmon/ it says:

The disk contains an unclean file system (0, 0).
Metadata kept in Windows cache, refused to mount.
Falling back to read-only mount because the NTFS partition is in an
unsafe state. Please resume and shutdown Windows fully (no hibernation
or fast restarting.)
Could not mount read-write, trying read-only

I originally formatted this drive in Windows, is that the issue? Ideally I'd use btrfs or zfs not ntfs, but here we are.

How do I get access again?