Issue with duplicate VAT/Tax lines when applying prepayments in ARInvoice report (Report Designer)

Hi everyone,

I am facing an issue with a customized ARInvoice report (Report Designer) in Haufe X360/Acumatica.
When a prepayment invoice (DocType = PP) is applied to a regular invoice, the tax section in the main report shows multiple tax lines.

Example:

• Net amount: 30.00 €

• Tax (19%): 5.70 €

However, in the tax section I get three lines:

• +5.70 (invoice tax)

• +5.70 (tax from prepayment)

• –5.70 (adjustment/correction line from prepayment application)

The totals are technically correct, but for the customer it looks confusing because the VAT/Tax is printed three times (see attached screenshot).
 

What I tried so far:

• Added a VisibleExpr in the tax section, e.g.:

  =IIf([ARInvoice.DocType] <> 'PP', True, False)

  → Unfortunately this did not solve the issue, the duplicate tax lines are still there.

• Checked if the issue is coming from the subreport → but it actually happens in the main report.

• It looks like the tax section is pulling from both ARInvoiceTax and the adjustments (ARAdjust), so the prepayment tax is included.

  
   

My questions:

• How can I make sure that only the actual invoice tax (ARInvoiceTax) is displayed in the tax section, and not the prepayment tax lines?

• Should I create a separate command/data source for prepayments, instead of letting them appear in the tax block?

• Is there a best practice for handling this scenario, so that only one tax line per TaxID appears in the main report, even if prepayments are applied?

Thanks a lot in advance for your support