Can't change root password using init=/bin/sh method from Grub2

I’ve got a new to me Lenovo Thinkpad T400 I’ve installed 13.2 on.
When I try to use the root password it fails.
So I googled and found a thread here on the forum that tells how to recover change my password.
At the Grub2 menu I hit “e” and then append init=/bin/sh to the line that starts with linux I hit F10 then it boots.
I issue passwd root and then enter the new password twice as prompted this then tells me:

passwd: Authentication token lock busy
passwd: password unchanged. 

How do I get around this? It’s a clean new install with no updates installed really except the very first small update that takes care of zypper. Reinstall?

I’ve got another question is it possible this laptop has some kind of BIOS lock that prevents getting root and administrating the OS on laptop?

I think it is reporting the existence of a lock file. When anything tries to update the passwd file, a lock file is created. It seems to be suggesting that, in addition to your process to change the password, there’s another process updating that file.

Now this is strange.
When I did the install I was sure I had a separate root password.
I tried my user pass and authed me and let me do a zypper up.

So I need to create a new root password using passwd after I’m logged in as root I guess?

That is the normal way for a user to change his/her password, be loged in and use the passwd command. That is also true for root:

su -

You root is mounted read-only. Normally it is remounted read-write as part of startup sequence but as you use /bin/sh as init that does not happen. Either append rw to kernel command line or manually remount it after boot before changing password:

mount -o remount,rw /