Gstr3b filed wout offset liability from cash ledger

Clive Sinclair (Self employed) (31 Points)

21 October 2017  

For Jul’17, I had filled GSTR1 and also paid the GST of Rs 36,000.
I paid GST vide CIN dtd 9 Aug’17 and then I filed GSTR3B vide ARN on 18 Aug’17.

Later I realised that I didn’t use Offset Liability option in Pt 6 of GSTR3B for Jul’17. Now I am unable to offset Liability and
hence Electronic Cash Ledger still shows a balance of Rs 36,000.
Kindly advise how do I offset this amount to GSTR3B for July now.
GST Helpdesk is helpless in answering my query.
I have filed correctly my GSTR3B for Aug and Sep by off-setting GST for Aug and Sep.

How can I Offset Liability for Jul'17 now?