Unicom card can't send and receive short messages and surf the Internet.

If you have tested the mobile phone card, it still doesn't work. You don't rule out that there is something wrong with the mobile phone card. In this case, it is suggested that you can bring your valid certificate to China Unicom's own business hall to change your card. I suggest you check your mobile phone balance. If the balance is insufficient, it may affect your use. If you owe money, it will take 48 hours to recharge the Internet.

If you can't send SMS at present, I suggest you set your SMS center number according to the screenshot below.

If it is not for the above reasons, I suggest you take your mobile phone and mobile phone card to Unicom's own business hall or mobile phone after-sales center to help you test it.