GSTR 3B (OUTWARD SUPPLY)

if in outward supply Assesse shows his taxable amount correctly but in cgst/sgst both the coloum put the total gst amount.

example:-
if outward supply is 100, gst on it 18 (cgst -9/sgst -9)
A person filled -
outward supply - 100
cgst - 18
sgst - 18

note - payment set off through credit ledger

How the taxpayer can claimback excess gst paid ?