Why my money is frozen?

When users carry on some actions, a certain amount of money in the users' wallets would be frozen. This frozen amount would be unable to be used for other transactions, till the related actions finish, successfully or in failure. After the related actions finish, the frozen amount will be unfrozen, or deducted from the user's wallet, completely or partly, depending on the circumstances.

Actions that would cause money to be frozen include, but are not limited to,

• Withdraw money: the amount to be withdrawn will be frozen, till the withdrawal request finishes (in success or failure);
• Sending an invitation for a tutoring lesson: the lesson fee will be frozen, till the invitation ends.