A Voucher Class has to be created to record adjustment entries related to Sales Tax.
Go to Gateway of Tally > Accounts Info > Voucher Types > Alter > Journal
In the Voucher Type Alteration screen, enter the Name of Class, for e.g., Sales Tax Adjustment
Set Use Class for Sales Tax Adjustments to Yes
Accept the Voucher Type Class screen
Accept the Voucher Type Alteration screen.
'Creating a Voucher Type to Adjust Sales Tax' has been shared with