Hello,
Please check the following factors that may cause abnormal time zones.
Network location configuration: The Windows operating system automatically configures location Settings, including the time zone, based on the network the user is connected to. If a Wi-Fi network's network location is incorrectly configured, it may incorrectly specify a time zone. Make sure that the network location of all computers is set correctly and that there are no incorrect configurations.
DHCP server Settings: DHCP servers can push location information to connected clients, which may affect time zone Settings. If two buildings use different DHCP server Settings, time zone differences may result. If possible, compare the configuration of the DHCP servers in the two buildings to see if there are any differences.
Windows Settings: Users or administrators may have manually changed the time zone Settings on some computers, or configured them through, for example, group policies. Make sure the time zone Settings are not manually changed, and check the group policy Settings.
Update your system: Make sure all your computers have the latest Windows updates and patches installed.