Cannot restore a snapshot - "file" is not a BTRFS snapshot

Several months ago I had to delete my Nextcloud instance for external reasons. Before that I took a snapshot to be able to recover all the files and the tags of each one (re-adding all tags is a multi-day job).

Now I have installed Nextcloud again and migrated the snapshot but I get an error saying “is not a BTRFS snapshot” in nc-restore-snapshot.

I am not finding so much information about this problem and the few possible solutions are not helpful. I am a student who, after several months, I am noticing the lack of practice with servers. I don’t remember the NC version of the snapshot and I don’t know if I can get that information from the snapshot itself. Any information to know what the problem is I will provide it. Thank you.

System Info:

NextCloudPi version v1.29.8
NextCloudPi image NextCloudPi_03-28-20
distribution Raspbian GNU/Linux 10 \n \l
automount yes
USB devices sda
datadir /media/myCloudDrive/ncdata
data in SD no
data filesystem btrfs
data disk usage 19G/932G
rootfs usage 37G/118G
swapfile /var/swap
dbdir /media/USBdrive/ncdatabase
Nextcloud check ok
Nextcloud version
HTTPD service up
PHP service up
MariaDB service up
Redis service up
Postfix service up
internet check ok

This is the content of the snapshot. I changed all permissions manually from root to www-data assuming it could be a permissions error. I can get information from any log that is required.