"Re-run setup" for "Storage Snapshots" returns Error

Hi all,

FBX Ver: 25.1 FreedomBox is up to date.
Installation image from FBX website for Raspi 4B
FBX installed on external SSD

In Plinth, Re-run setup for Storage Snapshots returns below error.

Error updating app: '.snapshots subvolume not found in /' 

Error running action: snapshot..setup(5): KeyError(".snapshots subvolume not found in /")
Action traceback:
╞   File "/usr/lib/python3/dist-packages/plinth/actions.py", line 398, in _privileged_call
╞     return_values = func(*arguments['args'], **arguments['kwargs'])
╞                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
╞   File "/usr/lib/python3/dist-packages/plinth/modules/snapshot/privileged.py", line 35, in setup
╞     _add_automount_unit('/')
╞   File "/usr/lib/python3/dist-packages/plinth/modules/snapshot/privileged.py", line 185, in _add_automount_unit
╞     subvolume = _get_subvolume_path(mount_point)
╞                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
╞   File "/usr/lib/python3/dist-packages/plinth/modules/snapshot/privileged.py", line 165, in _get_subvolume_path
╞     raise KeyError(f'.snapshots subvolume not found in {mount_point}')

lsblk -f output as below

NAME   FSTYPE FSVER LABEL UUID                                 FSAVAIL FSUSE% MOUNTPOINTS
sda                                                                           
├─sda1 vfat   FAT16       XXXX-XXXX                            100,3M    61% /boot/firmware
└─sda2 btrfs              XXXX-XXXX                            334,9G    24% /.snapshots
                                                                             /
sdb                                                                           
└─sdb1 ext4   1.0   disk1 XXXX-XXXX                              1,1T    33% /media/root/disk1
sdc                                                                           
└─sdc1 ext4   1.0   disk2 XXXX-XXXX                            206,8G    72% /media/root/disk2
sdd                                                                           
└─sdd1 ext4   1.0   disk3 XXXX-XXXX                            563,9G    33% /media/root/disk3
zram0                                                                         [SWAP]

df -h output as below

Filesystem      Size  Used Avail Use% Mounted on
udev            3,8G     0  3,8G   0% /dev
tmpfs           781M   76M  705M  10% /run
/dev/sda2       466G  111G  335G  25% /
tmpfs           3,9G  1,1M  3,9G   1% /dev/shm
tmpfs           5,0M     0  5,0M   0% /run/lock
/dev/sda1       256M  156M  101M  61% /boot/firmware
/dev/sdc1       916G  663G  207G  77% /media/root/disk2
/dev/sda2       466G  111G  335G  25% /.snapshots
/dev/sdd1       916G  306G  564G  36% /media/root/disk3
/dev/sdb1       1,8T  609G  1,2T  35% /media/root/disk1
tmpfs           781M     0  781M   0% /run/user/10000

fstab as below

UUID=XXXX-XXXX / btrfs compress=zstd:1 0 1
UUID=XXXX-XXXX /boot/firmware vfat errors=remount-ro 0 2
UUID=XXXX-XXXX /media/root/disk1 ext4 x-systemd.automount 0 2
UUID=XXXX-XXXX /media/root/disk2 ext4 x-systemd.automount 0 2
UUID=XXXX-XXXX /media/root/disk3 ext4 x-systemd.automaount 0 2

snapper works perfectly with no errors in creating or restoring snapshots.

Would anyone have any thoughts on this error and how to resolve it?
Thanks in advance.