Why does the Xiaomi Smart Band 10 Ceramic Edition display default icons when receiving notifications?

For your reference, here are the explanations about the principle of the icons displayed on the Xiaomi Smart Band 10 Ceramic Edition when receiving notifications:
1. The Xiaomi Smart Band 10 Ceramic Edition supports dynamically caching 20 notification icons. If the 21st message is received when 20 icons are cached, the band will delete the icon of the corresponding APP not receiving notifications for the longest time and cache the new icon of the corresponding APP;
2. At this time, if the APP of its icon being deleted receives notification again, it is necessary to request the icon again;
3. Therefore, if there are many APPs on the phone and messages are pushed regularly, you will view the default icon when the notifications are pushed on the band, the corresponding icon of the APP will be displayed in the notification center after the default icon is displayed on the global reminder interface. You can disable the notifications that are checked less.