Clarification Requested for E-Invoice Generation – Export with Payment

We are the Exporter of leather products, to get gst refund we opted refund through icegate and while GSTR1 we are using the method of Export with payment. While we are creating E-Invoice we have mentioned the all the details including shipping bill number, shipping bill date and Port Code. E-Invoice has been auto populated successfully to GSTR1 against export, but shipping bill number, date and port code not showing. Without this data gst refund through icegate cannot be processed. If I edit the E-Invoice by feeding the data then it will show warning message as follows "System has auto-populated the details from e-invoices reported to IRP. Any changes made in GSTR-1 will be marked as discrepancy. Do you want to Proceed?" 1. Why shipping bill data alone not auto populated in GSTR 1? 2. Can i edit the E-Invoice in GSTR 1, If not then what is the right procedure?