What does this short message sent by China Unicom mean?

Account balance refers to all the money on the mobile phone, including contract money, gift money, phone call refund, etc. The available balance of the account refers to the money that can be used for consumption in the current month except for some frozen money, and the consumption amount in the current month has not been deducted; The available advance payment is the remaining phone bill balance so far. Warm reminder: According to this short message, the current phone bill balance for the current month is 3 yuan.