What should I do if Doop guarantees that the car loan has not been paid back?

Try to repay the loan as soon as possible, because it will affect your personal credit. If the loan contract cannot be fulfilled and repayment is made according to the original repayment plan, you can apply to the lending institution for a reasonable extension of repayment. Generally speaking, as long as the reasons are reasonable, the lending institution will relax your requirements for a few days. Although no one is willing to borrow money, it is a matter that is both ungrateful and humiliating, but everyone has difficulties in forcing a hero to death with a penny.