ubuntu服务器：SSH横幅告诉更新包但没有更新

25 packages can be updated.
15 updates are security updates.

但是,如果我运行包升级/更新,则不会出现任何问题：

$sudo apt-get update
$sudo apt-get upgrade
...
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded,0 newly installed,0 to remove and 0 not upgraded.

在做了一些研究之后,我发现发布apt-get dist-upgrade可能有所帮助,但它没有任何区别.

欢迎任何帮助.