How does iphone delete SMS completely?

How to delete SMS at the bottom of iphone:

1, restart the phone:

After deleting the SMS, it is recommended to restart the phone. Restarting the phone is actually a process of clearing the system cache, and all previous usage records are cleared.

2. Modify the search scope:

Use iphone to enter settings->

General->; In spotlight search, unchecking this information will not create a cache for the information in spotlight search.

3. Language switching:

Use iphone to enter settings-> General->; Multilingual environment-> Language, first select another language (such as English), the system will refresh, and then repeat the operation to switch back. This method is only applicable to customers who know foreign languages, and is generally not recommended.