Why does the account text message show that the available balance does not match the actual balance?

Available balance of account: the available balance refers to the remaining available balance after deducting the monthly payment of special deposits account this month. Account balance: available account balance+frozen account balance. Frozen pre-deposit: refers to a certain amount of cash that users pay to China Unicom in advance according to the contract due to reasons such as nickname and contract plan. Specific suggestions can contact the local Unicom customer service. Tips: Upgrade 4G, with more traffic and lower tariffs. Click /sAbMP for details.