BR-CO-03: Both the VAT point date (BT-7) and VAT point date code (BT-8) are present, but…
What it means
Both the VAT point date (BT-7) and VAT point date code (BT-8) are present, but only one of them should be used at a time.
How to fix it
Remove one of the two: keep either BT-7 (an explicit date) or BT-8 (a code), not both.