Why are there still messages after all the messages have been deleted?

SMS deletion is not completed, and SMS notification is still displayed in the notification center.

1. When deleting the short message, it was not completely deleted from the device. Some devices will mark the deleted SMS as "deleted", but it actually remains in the storage space of the device. This means that you can't see the short messages in the short message list, and the short messages still exist in the device.

2. Some devices will still display relevant SMS notifications after deleting SMS. Notifications in the notification center will not be updated in real time and will be cleared after a period of time.