How to get FIRC certificate when payment received in INR

One of our client from Saudi Arabia had make the payment in INR through RTGS in our current account against export of one machine.  Now I want to know how to get the FIRC certificate for this payment. As our Bank has received the payment in INR through RTGS,  I guess our bank will not issue FIRC as they have not got any foreign remittence. 

Plz. help me on this issue. 

Thanks and regards

Sundeep Rajput