[Resolved]  Citibank Credit Card — Cheque lost by bank

Dear Sir,
My father Mr Shahaji l Nigde, I holds a credit card of citibank as an add on card holder.
Hr used the card on 23rd Oct 2009 to pay an amount of Rs 20, 086/-. He dropped a cheque for the amount at drop box at Chinchwad on 02 Mar 09. But the amount paid does not reflect in the statement issued by citibank on 14 Apr 09, instead they charged him for not paying on time and also levied a huge fine for it.
Plz suggest a solution.