Factory Reset an empty ReadyNAS NV+ v2

Hi all, it's my first post here - I wonder if you can help.

I'm trying to reset and completely wipe (of settings data) my old ReadyNas. I'm trying to give it a new home as I've had no need for it for a few years now,

Unfortunately I don't have any internal drives in the house that I can put in it - so it's currently diskless.

Is there a way to factory reset it without discs?

I've got to the on-screen reset menu and selected both OS reset and Factory Restore, but none of which seem to do anything. After a moment it just reverts back to the 'ERR: No disks detected' display.

I know that a reset hasn't worked, as when looking at the device on RAIDar the IP for the device is as i'd set it to. So it can't have reset - and I cant seem to access an Admin page via RAIDar or a browser or ReadyCLOUD.

I'm just looking to make sure it's set to a default for a new owner.

Thanks all.