Missing entries in previous year audit report

I have a question.If a firm accountant forget to update some payment details in balance sheet of the firm and the audit was done with these missing entries.so what the solution to correct this.i.e. (a person paid the ammount for goods in bank account.and the time of book keeping we forget to update their payment details and shows him as a debtors for next financial year)then how can we correct these errors.