24th Sept, 20..
Referring to your letter of 23rd August, 10th September and 20th September, I am sorry to inform you that as I was indisposed for nearly two months. I was unable to sign any cheque and no payment could be made during this period. I am now enclosing a draft for Rs. 975/- in full and final settlement of your bill.
I regret very much this delay in settling your account and hope you will not mind it as it was beyond the circumstances of my control.