1. Whether the SMS center number is set correctly, please enter the correct SMS center number;
Second, there is no signal or the mobile phone battery is insufficient;
3. The system is busy during the peak period of holiday SMS sending, so it is suggested that you try again later or avoid the peak period of sending;
Fourth, the mobile phone shields the short message sending function;
5. The other party's number is blacklisted;
6. Insufficient quantity balance;
Seven, SMS inbox and outbox are full.