无论我使用“sudo apt-get *”安装什么应用程序，终端都会显示以下内容
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies.
openssh-server : Depends: openssh-client (= 1:8.2p1-4)
Recommends: ncurses-term but it is not going to be installed
Recommends: ssh-import-id but it is not going to be installed
openssh-sftp-server : Depends: openssh-client (= 1:8.2p1-4)
scribus : Depends: scribus-data (= 1.5.5+dfsg-6build1) but it is not going to be installed
Depends: libgraphicsmagick-q16-3 (>= 1.3.5) but it is not going to be installed
Depends: libopenscenegraph160 but it is not going to be installed
Depends: libopenthreads21 but it is not going to be installed
Depends: libpodofo0.9.6 (>= 0.9.6+dfsg) but it is not going to be installed
Depends: libpython2.7 (>= 2.7) but it is not going to be installed
Depends: libqxp-0.0-0 but it is not going to be installed
Depends: libzmf-0.0-0 but it is not going to be installed
Recommends: fonts-dejavu but it is not going to be installed
Recommends: icc-profiles-free but it is not going to be installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).
但在我尝试“sudo apt --fix-broken install”之后，它总是显示为这样
Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
The following additional packages will be installed:
openssh-server openssh-sftp-server
Suggested packages:
molly-guard monkeysphere ssh-askpass
Recommended packages:
ncurses-term ssh-import-id
The following packages will be upgraded:
openssh-server openssh-sftp-server
2 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
2 not fully installed or removed.
Need to get 429 kB of archives.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Err:1 http://cn.archive.ubuntu.com/ubuntu focal-updates/main amd64 openssh-sftp-server amd64
1:8.2p1-4ubuntu0.4
404 Not Found [IP: 2001:67c:1562::18 80]
Err:2 http://cn.archive.ubuntu.com/ubuntu focal-updates/main amd64 openssh-server amd64 1:8.2p1-4ubuntu0.4
404 Not Found [IP: 2001:67c:1562::18 80]
E: Failed to fetch http://cn.archive.ubuntu.com/ubuntu/pool/main/o/openssh/openssh-sftp-server_8.2p1-4ubuntu0.4_amd64.deb 404 Not Found [IP: 2001:67c:1562::18 80]
E: Failed to fetch http://cn.archive.ubuntu.com/ubuntu/pool/main/o/openssh/openssh-server_8.2p1-4ubuntu0.4_amd64.deb 404 Not Found [IP: 2001:67c:1562::18 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?