I have tried to update via sudo apt update and I got this :
Get:1 https://brave-browser-apt-release.s3.brave.com stable InRelease [7,547 B]
Hit:2 http://archive.ubuntu.com/ubuntu noble InRelease
Err:1 https://brave-browser-apt-release.s3.brave.com stable InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 0686B78420038257
Hit:3 http://download.virtualbox.org/virtualbox/debian noble InRelease
Reading package lists... Done
W: GPG error: https://brave-browser-apt-release.s3.brave.com stable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 0686B78420038257
E: The repository 'https://brave-browser-apt-release.s3.brave.com stable InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
My /etc/apt/sources.list:
deb http://archive.ubuntu.com/ubuntu noble main multiverse universe restricted
deb-src http://archive.ubuntu.com/ubuntu noble main multiverse universe restricted #Added by software-properties
Nothing more and I have tried
sudo apt update
sudo apt autoremove
sudo apt upgrade
And I have tried so far but couldn't do anything feasible. Please help me whether I would be retrieve this system back to normal or do I need to reinstall ubuntu?
Thanks!
