我在 debian buster 上安装 libgnutls28-dev 包时遇到问题，apt 抛出以下内容：
Reading package lists... Done
Building dependency tree
Reading state information... Done
Suggested packages:
gnutls-bin gnutls-doc
The following NEW packages will be installed:
libgnutls28-dev
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 1,086 kB of archives.
After this operation, 4,417 kB of additional disk space will be used.
Err:1 http://deb.debian.org/debian buster/main amd64 libgnutls28-dev amd64 3.6.7-4
404 Not Found [IP: 151.101.220.204 80]
E: Failed to fetch http://deb.debian.org/debian/pool/main/g/gnutls28/libgnutls28-dev_3.6.7-4_amd64.deb 404 Not Found [IP: 151.101.220.204 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
让我烦恼的是该软件包可在http://deb.debian.org/debian/pool/main/g/gnutls28/libgnutls28-dev_3.6.7-4+deb10u2_amd64.deb 获得，出于某种原因，apt 是寻找libgnutls28-dev_3.6.7-4_amd64.deb而不是libgnutls28-dev_3.6.7-4+deb10u2_amd64.deb.
我尝试使用运行的特定版本apt install libgnutls28-dev=3.6.7-4+deb10u2并得到以下结果：
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Version '3.6.7-4+deb10u2' for 'libgnutls28-dev' was not found
问题是这从何而来？这是一个apt问题吗？还是它gnutls28误导了依赖关系？还是应该首先有一个文件libgnutls28-dev_3.6.7-4_amd64.deb？
[编辑]
根据 Knud 的评论添加此内容：
根据apt系统是最新的：
apt update
Hit:1 http://deb.debian.org/debian buster InRelease
Hit:2 http://deb.debian.org/debian buster-updates InRelease
Hit:3 http://security.debian.org/debian-security buster/updates InRelease
Hit:4 http://deb.debian.org/debian buster-backports InRelease
Reading package lists... Done
Building dependency tree
Reading state information... Done
All packages are up to date.
我与其中一个软件包维护者确认，可用版本_3.6.7-4+deb10u2 是最新版本，并且apt应该知道这一点，但是：
apt-cache policy libgnutls28-dev
libgnutls28-dev:
Installed: (none)
Candidate: 3.6.7-4
Version table:
3.6.7-4 500
500 http://deb.debian.org/debian buster/main amd64 Packages
所以这是一个apt问题。出于某种原因apt，即使拥有超级牛的力量，也会陷入过时的状态。任何指导将不胜感激。