I tried updating sources.list and modify server images in ubuntu software updater and still facing below errors while running sudo apt update
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal/InRelease Could not resolve '<proxy_server>'W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal-updates/InRelease Could not resolve '<proxy_server>'W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal-backports/InRelease Could not resolve '<proxy_server>'W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/focal-security/InRelease Could not resolve '<proxy_server>'W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/jammy/InRelease Could not resolve '<proxy_server>'W: Failed to fetch https://dl.google.com/linux/chrome/deb/dists/stable/InRelease Could not resolve '<proxy_server>'W: Some index files failed to download. They have been ignored, or old ones used instead.Can anyone help with this? Thanks in advance.