Unable to install pt-devices on Ubuntu

I have a new Pi-Top and am running Ubuntu Desktop (which I have to use). I have followed the instructions to add the pi-top drivers but I keep getting this error:

greg@greg-desktop:~$ sudo apt install --no-install-recommends -y pt-device-manager pt-sys-oled pt-firmware-updater
Reading package lists… Done
Building dependency tree… Done
Reading state information… Done
E: Unable to locate package pt-device-manager
E: Unable to locate package pt-sys-oled
E: Unable to locate package pt-firmware-updater

Can someone please tell me how to get this to work! It’s esential to a project I’m working on!

Greg

Hi Greg, I know you’ve sent me the screengrab privately, but if you shared it here it might help.
(I can’t share it for GDPR Reasons)