The setup method and reasons are as follows:
1. please go to [Settings] >> [Bluetooth] >> tap the [>] icon on the right side of [Xiaomi Buds 5] >> [Additional settings] >> enable [Show on Notification shade].
2. The battery level display feature in the notification shade is not supported by all phones. If your phone does not support this feature, the battery level will not be displayed.
Note:
When the earbuds are out of the charging case, the APP only shows the earbuds’ battery level. When the earbuds are placed back into the case, the APP will display the battery levels of both the earbuds and the charging case.