If it is a 4G card, it should display Level 4. What I want to say is that 3G should be a problem with the mobile phone system. You can try to upgrade the system. Or in a network setting. Find it. If it still doesn't work, it's the phone hardware. Need after-sales service! If it is a 4G card, it should display Level 4. What I want to say is that 3G should be a problem with the mobile phone system. You can try to upgrade the system. Or in a network setting. Find it. If it still doesn't work, it's the phone hardware. Need after-sales service