Dear community.
I have problems restoring my backup:
Running nc-restore-snapshot
Nextcloud is in maintenance mode - no apps have been loaded
Create a readonly snapshot of ‘/media/data/ncdata’ in ‘/media/data/ncdata/…/ncp-snapshots/autobackup_2022-02-19_155430’
snapshot autobackup_2022-02-19_155430 generated
Maintenance mode already enabled
ERROR: Not a Btrfs subvolume: Invalid argument
Done. Press any key…
but “/media/data/ncdata” seems to be a subvolume…
root@nextcloudpi:/# btrfs subvolume list /media/data
ID 259 gen 40 top level 5 path ncdata
ID 261 gen 31 top level 5 path ncp-snapshots/manual_2022-02-19_152742
ID 262 gen 32 top level 5 path ncp-snapshots/manual_2022-02-19_152753
ID 263 gen 34 top level 5 path ncp-snapshots/hourly_2022-02-19_153601
Maybe someone give me a hint, how to face this error. 