Huawei
Set Time Zone Manually auf Huawei
Huawei phones read the time zone automatically from the mobile network you are currently connected to.
That works fine while traveling with an active SIM, but it breaks on Wi-Fi-only devices, in airplane mode, or when a local SIM reports the wrong region. In those cases the clock can be off by a full hour or more.
To correct this, you first need to turn off the automatic detection. Otherwise EMUI overwrites any manual entry again within seconds.
Menu path:
Settings ➔ System & updates ➔ Date & time ➔ Deactivate automatic ➔ Time zone ➔ Choose a time zone
Once the automatic switch is off, tap Time zone and select the correct region from the list. The change applies immediately across the whole system, including clock widgets and calendar entries.
Leave automatic detection turned on if you travel often and want the clock to adjust by itself once you land. Switch to manual only when the network reports the wrong location or when no signal is available at all.