Restoring failed

[yarii]

After trying to restore zst backup I got:

TASK ERROR: unable to restore CT 606 - command 'set -o pipefail && cstream -t 41943040 | lxc-usernsexec -m u:0:100000:65536 -m g:0:100000:65536 -- tar xpf - --zstd --totals --one-file-system -p --sparse --numeric-owner --acls --xattrs '--xattrs-include=user.*' '--xattrs-include=security.capability' '--warning=no-file-ignored' '--warning=no-xattr-write' -C /var/lib/lxc/606/rootfs --skip-old-files --anchored --exclude './dev/*'' failed: exit code 2

What can I do with that?

 

[yarii]

I tried to restore privileged to unprivileged container.
Is it supported?

If not how to convert one to another and vice versa.