Plz help

A proprietorship firm has supplied chemical to a public sector company. The terms of payment was bill discounting under letter of credit through a nationalised bank upto a limit of Rs 10 Lakhs.

As per the terms the supplier made the supply and received the payment through bank under LC. But the public sector company didn't made the payment to the bank and became defaulter to the bank.

And after two years , the supplier while applying for loan in other bank comes to know through his cibil report that he has been also been made defaulter by the bank for Rs 10 lakhs that he received under LC.

And thus as the cibil report is poor, the supplier is not getting the loan through other bank.

So, please give the remedy or any legal aspect for the buyer as he was only the Principal Debtor and he has nothing to do with the payment to bank.