In company code &1, the cash discount amount contains tax

What causes this issue?

In company code &v1&, the cash discount is calculated on the gross
amount. This distorts the results of profit simulation.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Procedure for System Administrators

Cash discount conditions are not taken into account in profit
simulation if you remove the "Calculate cash discount" indicator in
Customizing for the profit group.

Error message extract from SAP system. Copyright SAP SE.