Unicom's mobile phone is in arrears in February. Why can I send text messages?

Do not rule out the need for balance. Mobile phone downtime can be divided into two types: mobile phone half downtime and mobile phone full downtime. The mobile phone is semi-turned off, and it can receive short messages and answer calls, but it can't make calls, send short messages and surf the Internet. When the mobile phone stops completely, all services cannot be used. I suggest you recharge it in time.