How to encrypt the incoming call information of one plus 8t mobile phone?

1. First, click the settings icon, and then click Security and Privacy.

2. Second, click More Security Settings in the last column.

3. Then, after clicking, more options will appear. Select Encrypted Call to enter the encrypted call interface.

4. Finally, slide the button on the right side of the encrypted call to open it. You need to restart the phone after opening it. Click Open to restart.