Gst invoice

HI,

dear sir I have collected amount on which I didn't received Gst. Now my recipient not intended to pay Gst.
he credited amount with out Gst after deducting TDS.

now being a registered taxpayer how can I raise invoice on that amount.

Is I have to pay Gst on that amount?
If I have to disclose this invoice in B2B COLOUMN or B2C COLOUMN?