When logging into CCP > Home tab, the following warning can be seen:
Please be aware that your current balance amount -$ 102.22 is less than a minimum recommended amount of $ 0.00. Your services may be stopped. Please top up your account balance.
But there are no unpaid invoices or debit documents for this account.
FEA_CalculateNip is enabled on the installation. Every day the system checks the resources overusage and generates a NIP order, which is not seen in the control panel, but allows the customer (and the provider) to be aware of current resource usage and the fees the customer is supposed to pay. With each daily billing NIP order is recalculated according to the new resource usage. Basically, the number you see is accurate for the time of last daily billing, it grows according to the usage.