Why does Apple still display 1 17 unread items after deleting mobile phone information?

Unread message cache, error counter, short message filter.

1. unread message cache: after deleting the short message, the phone still keeps the unread message cache.

2. Counter error: The information counter of the mobile phone is inaccurate, which leads to the display error of the number of unread messages, which is caused by the error of the system or application.

3. SMS filter: Some SMS filters or applications mark some SMS messages as unread, even if they have been deleted.