Why can't Charm Blue note2 network fault messages be sent out?

Charm Blue note sends a short message to prompt the network failure because there is a problem with the number of the short message center. The solution is 1. Click the SMS icon on the mobile phone desktop; 2. Click on the three points in the upper right corner, and then select Settings; 2. Click on the SMS center at the bottom; 3. If there is a problem, click which card to set; 4. Call 10086 for the center number of the SIM card, then modify or add it, and then click OK below.