The balance of 4,800 yuan that became a bad debt was mainly due to the fact that the user still owed 4,800 yuan in the bank, which was not returned in time and eventually became a bad debt.

Credit card becomes a bad debt, which means that the cardholder's credit card has long-term unpaid bills, and the bank defaults that the bills cannot be recovered but does not give up the right to recover them, so it is recorded as a bad debt.

For reference only, there is no authoritative data.