Tanks @smu44 for your help,
I try to know which directory to check and I’m impressed :
There are to many answer to my umount
command
mount rootfs on / type rootfs (ro,seclabel,size=1680620k,nr_inodes=420155) tmpfs on /dev type tmpfs (rw,seclabel,nosuid,relatime,size=1816712k,nr_inodes=454178,mode=755) devpts on /dev/pts type devpts (rw,seclabel,relatime,mode=600) proc on /proc type proc (rw,relatime,gid=3009,hidepid=2) sysfs on /sys type sysfs (rw,seclabel,relatime) selinuxfs on /sys/fs/selinux type selinuxfs (rw,relatime) /sys/kernel/debug on /sys/kernel/debug type debugfs (rw,seclabel,relatime) none on /acct type cgroup (rw,relatime,cpuacct) tmpfs on /mnt type tmpfs (rw,seclabel,relatime,size=1816712k,nr_inodes=454178,mode=755,gid=1000) none on /config type configfs (rw,relatime) none on /dev/cpuctl type cgroup (rw,relatime,cpu) none on /dev/cpuset type cgroup (rw,relatime,cpuset,noprefix,release_agent=/sbin/cpuset_release_agent) pstore on /sys/fs/pstore type pstore (rw,seclabel,relatime) /dev/block/sda14 on /system type ext4 (ro,seclabel,relatime,norecovery,errors=panic) /dev/block/sda3 on /efs type ext4 (rw,seclabel,nosuid,nodev,noatime,discard,journal_checksum,journal_async_commit,noauto_da_alloc,data=ordered) /dev/block/sda15 on /cache type ext4 (rw,seclabel,nosuid,nodev,noatime,discard,journal_checksum,journal_async_commit,noauto_da_alloc,errors=panic,data=ordered) /dev/block/sda18 on /data type ext4 (rw,seclabel,nosuid,nodev,noatime,discard,journal_checksum,journal_async_commit,noauto_da_alloc,errors=panic,data=ordered) /dev/block/sda13 on /persdata/absolute type ext4 (rw,seclabel,nosuid,nodev,noatime,journal_checksum,journal_async_commit,noauto_da_alloc) tmpfs on /storage type tmpfs (rw,seclabel,relatime,size=1816712k,nr_inodes=454178,mode=755,gid=1000) /data/media on /mnt/runtime/default/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=1015,multiuser,mask=6) /data/media on /storage/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=1015,multiuser,mask=6) /data/media on /mnt/runtime/read/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=9997,multiuser,mask=23) /data/media on /mnt/runtime/write/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=9997,multiuser,mask=7) /dev/block/vold/public:179_1 on /mnt/media_rw/F0E9-334E type vfat (rw,dirsync,nosuid,nodev,noexec,relatime,uid=1023,gid=1023,fmask=0007,dmask=0007,allow_utime=0020,codepage=437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro) /mnt/media_rw/F0E9-334E on /mnt/runtime/default/F0E9-334E type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=1015,mask=6) /mnt/media_rw/F0E9-334E on /storage/F0E9-334E type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=1015,mask=6) /mnt/media_rw/F0E9-334E on /mnt/runtime/read/F0E9-334E type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=9997,mask=18) /mnt/media_rw/F0E9-334E on /mnt/runtime/write/F0E9-334E type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=9997,mask=18)
I really don’t know what to do with it and don’t want to break anything.