automatic refund of gst on export with payment of tax not received

shah (student) (621 Points)

10 August 2019  
One of my new client whose previous GST return filed by some one else
In period 2017-18
He exported goods WITH PAYMENT OF TAX

but previous accountant forgot to feed SHIPPING BILL AND PORT CODE

Therefore no automatic refund of tax paid received by client


Now is there any other way to claim

As amendment in GSTR 1 table 9A not showing option 2017-18

What to do any idea?