Question: Why is it not possible to manually change the VAT amount in the invoice, although it is possible in the invoice received?

Answer: The reason is the different role of these documents in accounting and tax requirements.

For invoices, the system enforces strict rules because:

1)VAT is legally sensitive (affects your tax liability)

2) It must be calculated consistently from:

-tax rate

-taxable base

3) Manual edits could:

-break compliance

-cause incorrect tax reporting.

So the system locks VAT calculation to prevent user mistakes and ensure correct posting to tax accounts.

For invoices received, the situation is different:

1) You are recording supplier data, not generating it

2) Supplier invoices may:

-have rounding differences

-include corrections

-be issued from different systems

Therefore, the system allows manual VAT adjustment to match the supplier’s actual invoice (hard copy).

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