What does the alarm mean when the charge control balance is lower than the alarm threshold?

The electricity bill is running out. When the customer's pre-stored balance is less than the alarm threshold, the fee control balance is lower than the alarm threshold, and the system will automatically send an alarm message to remind the customer to pre-store the electricity fee. Cost control refers to planning, restricting and adjusting the elements that constitute the cost in the process of production and operation, correcting the deviation in time, controlling the cost overrun, and controlling the actual consumption within the scope of the cost plan.