mount – Strange unmount when i run a python3 script on systemd


I have a python script to auto backup my server. In this process, It need to mount a disk.

When i run it on terminal, There have no strange ntfs message, also no strange unmount.

(Action) Mounted Backup Disk.
(Action) Stopped Servers.
(Action) Maked new backup dir.
(Action) Copied servers.
(Action) Started Servers.
(Action) Copied mods.

But when i run it as a systemd service, a lot of strange thing appears:

Sep 09 07:26:14 etc.host.example ntfs-3g(107319): Mount options: allow_other,nonempty,relatime,rw,fsname=/dev/sdb1,blkdev,blksize=4096
Sep 09 07:26:14 etc.host.example ntfs-3g(107319): Ownership and permissions disabled, configuration type 7
Sep 09 07:30:22 etc.host.example python3(107303): (Action) Mounted Backup Disk.
Sep 09 07:30:22 etc.host.example python3(107303): (Action) Stopped Servers.
Sep 09 07:30:22 etc.host.example python3(107303): (Action) Maked new backup dir.
Sep 09 07:30:22 etc.host.example python3(107303): (Action) Copied servers.
Sep 09 07:30:22 etc.host.example python3(107303): (Action) Started Servers.
Sep 09 07:30:22 etc.host.example python3(107303): (Action) Copied mods.
Sep 09 07:30:24 etc.host.example ntfs-3g(107319): Unmounting /dev/sdb1 (Cato Save)
Sep 09 07:30:24 etc.host.example systemd(1): backup.service: Succeeded.

It also unmount my /dev/sdb1 after copy! Why?


Edit: More info