@Anonymous
The expression looks okay to me. Can you please verify if the spelling in the text values is correct?
Can you do a test and share the results with me?
Add four test labels on your screen and add the text value as:
Label1 -> Or(DataCardValue74.Selected.Value="Regnskabs- og Plantekunde",DataCardValue74.Selected.Value= "Regnskabskunde")
Label 2 ->IsBlank(ThisItem.'Ø90-nr.')
Label 3 -> IsBlank(ThisItem.'Kontoplan nr.')
Label4 -> IsBlank(ThisItem.Branchekode)
Please share a screenshot of the results so that we may help you better.
Hope this Helps!
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