Accounting for Extraneous debits

Amit (84 Points)

10 May 2007  
We had sent consignment to parties via L/c's. the collecting banker with whom we have an account credited the same at full amount bur debited amount in respect of interest which it received less from the issuing banker. On taking up the case our banker has agrred to refund the same but till 31/03/06 not refunded. How will the same shall be same in accounts? Also, if some of the amount is not refunded, how it shall be treated in the books and for which year? Pl. comment.