Xiaomi
Set Default Reminder Time for Calendar Events auf Xiaomi
The Calendar app on Xiaomi phones applies one fixed reminder time to every new event automatically. This value comes from a global setting inside the app, not from the event itself, which is why it stays the same until you change the preference directly.
If you keep switching the reminder manually after creating an event, you are working around this default instead of fixing it. Adjusting the setting once removes that extra step for every future entry.
Where to change it
Open Open the Calendar app ➔ Open the menu ➔ Open the Settings ➔ Tap on Default reminder time ➔ Set the Default reminder time. Pick the option that matches how far ahead you usually want to be notified, such as 5 minutes before.
This setting only affects new events created after the change. Existing appointments keep whatever reminder time was set when you added them, so you still need to update those manually if needed.
If different events need different lead times, for example a quick call versus a full-day trip, plan to adjust the reminder per event instead of relying only on the default. The default is best treated as a baseline for your most common case.