Refund voucher in GSTR1

Santosh Gill (Consultant) (37 Points)

25 July 2019  
Advance received in March 2019 against services on which GST was duly paid However, the project got cancelled & we had to 100% refund the advance amount, in June 2019.
My query is where to show the refund voucher in GSTR1? We have opted for quarterly GSTR1 filing.
Pls. advise.