R D S wrote:
Plugged it into laptop (Ubuntu) though, heard the usual noise as if it
had been recognised but it isn't visible in files.

Gparted doesn't seem to see it.

Smartmon says "Read device identity failed".

I think the last is that it doesn't respond to SMART commands, which most
pen drives don't anyway. However gparted not seeing it isn't encouraging.

Open a terminal, then plug it in. Immediately afterwards, type 'dmesg' and
press enter. Then post the last 20 or so lines here. This is the
kernel's log when it tries to talk to it, which should tell us what's going
on.

Theo