My Unicom mobile phone card received a text message reminding me that my account deposit was used up. What does this account deposit mean?

Pre-deposit for opening an account is the initial fee for customers to open an account with a mobile phone card. Because there are different degrees of discounts for card opening through various channels, the deposit for opening an account is limited to the handling fee for offsetting this number. When a mobile phone user handles the consolidated account business, the remaining amount of pre-deposit after opening an account is only available at this number; For mobile phone users who join the converged package, the remaining deposit for opening an account can only offset the expenses outside the package of this number, and cannot offset the expenses of other numbers under the * * * account. Except for deposit, all the numbers under the account can be used for ordinary prepaid phone calls paid by customers through various payment channels The deposit in advance for opening an account cannot be sold back or refunded, nor can it be used to transfer telephone charges to the gambling business.