I just bought the Unicom 5 yuan card today, so I can't make phone calls or send text messages. What is the reason?

I suggest you change your mobile phone and test your Unicom card. If it still doesn't work, it doesn't rule out that the mobile phone card is faulty. If the card is cut, it may also cause damage to the mobile phone card and affect the use. In this case, it is recommended that you bring your valid certificate to China Unicom's own business hall to change your card. If your mobile phone card can be used normally, there may be something wrong with the network settings of your mobile phone. I suggest you restore the mobile phone network; At the same time, it is suggested that you choose "automatic network selection" and "GSM only" modes in the network options, and you need to ensure that your mobile phone can support Unicom's network. In addition, if you use a locked version of iphone, it may be that the card sticker does not match the system after your system upgrade, which affects your use. In this case, I suggest you consult the mobile phone after-sales staff.

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 are in a weak area covered by Unicom signal, it may affect your use.

If you can't send SMS at present, you can set your own SMS center number as shown 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.