Gst refund on credit note

We had supplied one consignment in the month of Jan'2018 . The vehicle caught by authority and got seized by police . In the month of Dec'18 the said vehicle got released by court and the customer refused to receipt the material for obvious reason. So we had taken back the material at our place of supply in the month of Jan'19.

Now my questions are:-

1. Can we issue credit note to the supplier &

2. Can we claim GST refund on the basis of the credit note.