How to refuse each other by blackmail SMS?

1. First, open the received message. There is a contact icon in the upper right corner. Click to enter.

2. Secondly, after clicking, you can see that there are three icons below. Select the last one and the circle will be drawn! Icon, where you can set it.

3. After finally entering, pull it to the end. There is a number that can block this call. Click it, and then confirm to block the contact. You can block messages sent by this number, so you won't receive messages sent by this number next time.