Year end vendor reconciliation - Discount i

Hi
Doing creditor reconciliation for fy 19-20. And found some issues like turnover discount (CRN)in March Rs 81493 with gst but the same is not reflecting in our books. We are taking this in our Aug 20 return. My query do we need to pass entry in March 20 to match with the creditor statement. Plse advise what journal entry need to pass. TQ