early reply needed because of last date

I made inter state sale but make intra state purchase.

so I set off igst against cgst and sgst
but as we all know first we have to set off cgst against igst and then to use igst
my all cgst balance gets exhausted but I have near about Rs.50000 in sgst

now I come to know that I claim excess ITC in December month Of RS 20000.( cgst RS.10000 and sgst RS.10000). I think to correct it in Feb month. whether I need to pay interest
if yes then I have to pay only interest on excess cgst utilized because my sgst is still excess

but when I fill interst column cgst column will also get automatically filled up? what can I do