Sales Order going through without Credit hold

Hi,

We are using JD Edwards version 9.2 system and I have below questions

An order where the Net value of the SO did not exceed the credit limit of the Bill to, and hence Credit hold was therefore not applied.

Only when VAT was added to the net value and posted to the customer ledger after Sales update was the credit limit then exceeded, causing overtrading.

For Example#

Credit limit set for Customer is $100, Order created for the customer valued $90 and hence Credit hold was not applied, This order has 12% tax. After Sales update total amount due from customer is $100.8( $90 + $10.8= $100.8) which is exceeding credit limit of the customer resulting in overtrading.