Samsung i939 obtained permission to change the SMS application.

1. Under mobile phone operation: Settings-Application Manager-Slide Screen Option (All)-Find Information-Click Enter to try to clear the data.

2. If the problem still exists (caused by third-party software), please back up the data of the mobile phone (phone book, SMS, multimedia materials, etc.). ) and try to restore the phone factory settings (Settings-Reset-Restore Factory Settings).

Note: all the data stored in the mobile phone is lost, so it must be backed up to the sim card and sd card in advance before operation.

If the problem still exists, it is recommended to bring three purchase vouchers and send the mobile phone to the nearest Samsung service center for testing.