以下一段在会计书上的不是很懂：

A direct debit is also used by the bank when a dwposited cheque from a customer 'bounces' because of insufficient funds. In such a case, the cheque is marked as a dishonoured cheque(not sufficient funds) by the customer's bank and is returned to the depositor's bank. The bank then debits the depositor's account, as shown by the dishonoured cheque entry on the bank statement in figure 1. The bank sends the dishonoured cheque and direct debit to the depositor as notification of the charge. The dishonoured cheque creats an account receivable(from the bad cheque writer)for the depositor and reduces cash in th bank account.

Bank Statement
Date   Transaction                   Debit                Credit                 Balance
...
27/4    Deposit                                     |       1545.57       |         16232.41
29/4  Dishonoured Cheque       425.60     |                         |         15806.81
29/4   Deposit                                      |     2929.45           |  18736.26
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[size=13.63636302948px]不是很懂direct debit， customer , depositor 在这里究竟是什么意思，为什么明明够钱还是[size=13.63636302948px] Dishonoured Cheque，而且direct debit ？？
[size=13.63636302948px]请教大神们，谢谢，春节快乐！