When ownership is changed from a foreign user namespace, uid/gid numbers cannot be mapped and fall back to nobody/nogroup.
Using absolute paths like this bypasses the user namespace applied by Podman: it is a dangerous approach.
Try to revert it to a known ownership (root:root) with
chown -c samba1:samba1 /home/samba1/.local/share/containers/storage/volumes/shares/_data
Then repeat the commands I gave you previously.
Namespaces are important to understand the rich environment of containers, where service processes run: namespaces(7) - Linux manual page