I'm Samsung s4. How do I know whether my message was sent successfully and whether the other party received it? I am Unicom's card!

When sending a short message, you can set the send report to know whether it was sent successfully, and click Information-Settings-Send Report; As for whether others have received it, it is hard to say. The short message has been sent, and Unicom's system has received it and is ready to send it. But if the phone is in arrears or the number of the SMS center is wrong, I'm sorry, your SMS may not be received! And Unicom's system can only keep short messages for 48 hours. If the other party's mobile phone number is turned off or there is no signal, the mobile phone is in an abnormal state, and the other party can't receive the short message after 48 hours. You should also pay attention to this.