Input ITC Claimed but payment not paid to suppliers

Mohanraj J (1162 Points)

01 April 2021  
Dear Friends,
We supplied goods to our customer since Feb'20 to Mar'21. Our customer paid payment promptly to us for first 3 months only, after that they didn't make any payment to us, but claimed ITC for our sales invoices. As of now we paid GST about 12 Lakh particularly this customer only, and stopped to issue invoice for last 3 months. Anyone can assist me now, it is possible to revise the GST invoices? or any other suggestions?