when i “sudo apt-get update failed”,it show me(E:Failed to fetch http://ppa.launchpad.net/wengxt/fcitx-nightly/ubuntu/dists/xenial/main/binary-arm64/Packages 404 Not Found. E:Failed to fetch http://ppa.launchpad.net/chromium-daily/stable/ubuntu/dists/xenial/main/binary-arm64/Packages 404 Not Found. E:Some index files failed to download. They have been ignored ,or old ones used instead.)
i had change the URL ,but it didn’t work,also have some Err like these.
How can i fix it?thanks.