I understand that in given case you type SGST Input credit as INR 600 which is typo error. I assume it to be IGST input Credit INR 600. With this understanding, IGST ITC of INR 600 will be use to pay IGST of INR 400, CGST of INR 100 and SGST INR 100.
Request you to refer my above reply, I address your question. I just added one understanding of your question. If have any further query then request to re frame it