Fuse umount not working

Debian 12
Linux 6.1
Sysbox 0.6.2
Arch amd64

docker run -it --rm --runtime=sysbox-runc --device=/dev/fuse `docker build -q - << EOF
FROM debian
RUN apt-get update && \
	apt-get install -y --no-install-recommends systemd-sysv dbus kmod fuse gocryptfs && \
	echo 'root:123' | chpasswd && \
	mkdir /root/gocrypt /root/gocrypt-mnt && \
	/bin/echo -e '123\n123' | gocryptfs -init /root/gocrypt
STOPSIGNAL SIGRTMIN+3
ENTRYPOINT ["/sbin/init"]
EOF`

root@30511579335b:~# echo '123' | mount -t fuse.gocryptfs gocrypt gocrypt-mnt
Reading Password from stdin
Decrypting master key
Filesystem mounted and ready.
root@30511579335b:~# umount gocrypt-mnt
umount: /root/gocrypt-mnt: no mount point specified.
root@30511579335b:~# mount | grep gocrypt
/root/gocrypt on /root/gocrypt-mnt type fuse.gocryptfs (rw,relatime,user_id=0,group_id=0,max_read=131072)