How to show refund received in ITR due to return being revised

Dear Experts,

My client has filed IT return(Salary) and received refund for AY 20-21.

Now the department sent message stating that he has not disclosed certain interest income in

the return( SB Interest) as reported by the bank .  Now he wants to revise the return considering

the SB interest and pay the taxes.

Now the question is where to show the refund received in ITR as he has to payback the refund

received.

Please clarify.

regards

P Narayanan