Unable to edit tax condition set

Summary:

Hello,

We have a requirement to define and update tax box allocation rules for several tax conditions as per some So. European legal requirements.

So I attached 2 existing tax codes (one VAT and the other offset) to a newly defined tax condition set for purchase transactions and attached this tax condition set to an existing rule. However, on the tax box return preparation report, the amounts show 0.00.

Logged an SR and Oracle think it has to do with the fact that both the VAT and offset conditions point to the same tax box numbers. So I want to change this to the correct tax box numbers.