"According to this good friend, Wang Lu first only applied for one credit card. When the overdraft amount on this card could not be repaid, Wang Lu then applied for a new credit card, using the overdraft from the new card to pay off the old debt.
The bank card used for the automatic transfer service for loan repayments somehow turned into a credit card, leaving the user completely unaware after overdrawing it, and after several years, the interest ended up being higher than the principal."