Why can't Xiaomi's mobile calendar be updated?

It may be because of these four reasons:

The mobile phone is not connected to the internet, and the update of the mobile phone calendar needs to be connected to the internet. If your network doesn't work, or if you stop the traffic automatically without the phone bill, the calendar won't be updated.

You may not allow the mobile calendar to connect to the Internet. This needs to be checked in the settings. Go to Security Center, Network Assistant, find the calendar, click Allow at Network Permissions, then refresh and try again.

There may be an error in the calendar system. Clear the data of the calendar system, and then refresh.

It may also be because there is something wrong with the mobile phone system. You can turn it off and restart it, or you can ask the staff at the maintenance point.

I think the biggest possibility is that the calendar is not online. You can try all four reasons, and the calendar should work as usual.