Why Unicom 3G card sends SMS to telecom users, and why telecom can't receive SMS?

Unicom 3G card actually sends short messages to users of which operator, as long as they are normal users. If you send a short message to a telecom user with Unicom card, he won't receive it. Generally, if you can send it to other users normally, they can also receive it normally. But if your friend can't get the message, it's your friend's problem. Maybe his mobile phone is broken, or maybe his telecom short message center number is wrong. I suggest you ask him to change his mobile phone and see if he can send and receive text messages. If you can send and receive short messages, I suggest you plug the card back into your mobile phone and send yourself a short message to see if you can receive it. If not, I suggest that your friend can check whether it is a sim card problem. Then check whether the number of SMS center is set correctly. Excluding the above situation, it is recommended to take your mobile phone card to the local business hall for testing or replacement.