Apt update gives error on Ubuntu-Server

Hi Radxa Team,

When I run sudo apt update on freshly installed Ubuntu Server (legacy version 4.4: rockpi-4b-ubuntu-focal-server-arm64-20220401-0346-gpt.img.xz), it gives me GPT error.

I tried solution here: Apt error with latest buster image

wget -O - apt.radxa.com/focal-stable/public.key | sudo apt-key add -

But error doesn’t disappear. Can you check?

Several days ago everything was working fine.

Edit: Tried with Linux 5.10 image, it has same error too.

The key just expired today
sig sig b99c4befec47e96e 2020-11-24T02:10:06Z 2022-11-24T02:10:06Z ____________________ [selfsig]

So radxa needs to update it

They are working on this

And it would be nice to add instructions here:

Answer given here: Sudo apt update get error