How to restore the Apple SMS program when it is deleted?

What needs to be determined is whether to delete the short message content or delete the program. If the content is deleted, the recovery method is as follows:

Method 1: Open the iTunes software and connect the mobile phone to the computer. After the connection is successful, click the small mobile phone icon in the upper left corner of the window, then select "This machine", click the "Back up now" button, and then click "Don't back up the application" in the pop-up window. That is, click 1, 2, 3 and 4 in the figure below.

Method 2: Restore by third-party software.

If the SMS system is deleted, you can call Apple's designated repair shop to handle it.