Go to Tax -> Tax Code Maintenance
Here to Add the Tax Code
For Sales add as SR8 and make sure the rate is 8%
For Purchase add as TX8 and make sure the rate is 8%
On 01Jan2023
Change the Default Tax in Tax code
In Debtor Maintenance
Update 1 by 1 customer in this tax code
**Same Step in Creditor Side**
After done when user create the invoice then will auto show out the new tax code