How to set the password lock for Charm Blue 2 SMS?

You can add a program lock in SMS software.

Enter phone settings-> Security->; To apply encryption, select a program to encrypt. The password for applying encryption is the same as the password for locking the screen!

For systems higher than Flyme4.5, you can set a new password by applying encryption. If you forget the password, you can get it back in the same way.

The Flyme5 system can also use the document locking area function for photos, videos and documents. Open the document, press and hold the folder or file that needs to be kept secret, and select more-> Move to the lock area, and you need to enter a password before reading related files.