Thiruvananthapuram GSTAT Allows Cashew Exporter to Recover IGST Paid Twice Due to Clerical Errors in GST Returns - SAG Infotech Official Tax Blog. Thiruvananthapuram GSTAT Allows Cashew Exporter to Recover IGST Paid Twice Due to Clerical Errors in GST Returns SAG Infotech Official Tax Blog.