刚刚安装 Ubuntu 18.04，当我运行命令时sudo apt update，显示以下错误：
sudo apt update
Hit:1 http://linux.teamviewer.com/deb stable InRelease
Get:2 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB]
Hit:3 http://sg.archive.ubuntu.com/ubuntu bionic InRelease
Get:4 http://sg.archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB]
Get:5 http://sg.archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]
Reading package lists... Done
E: Release file for http://security.ubuntu.com/ubuntu/dists/bionic-security/InRelease is not valid yet (invalid for another 7h 31min 57s). Updates for this repository will not be applied.
E: Release file for http://sg.archive.ubuntu.com/ubuntu/dists/bionic-updates/InRelease is not valid yet (invalid for another 7h 32min 53s). Updates for this repository will not be applied.
E: Release file for http://sg.archive.ubuntu.com/ubuntu/dists/bionic-backports/InRelease is not valid yet (invalid for another 7h 34min 12s). Updates for this repository will not be applied.
有人知道是什么原因导致了这个问题以及如何解决它？