edited 12/09/19 in Smartsheet Basics

sum all values in OverUnder column if a specific artist is assigned in the Artist column

=SUMIF(Artist:Artist, Artist2, OverUnder20:OverUnder500)

returns error #incorrect argument set

If I remove the range numbers from OverUnder it works (until I add another expression in the same column then it produces a circular reference). With the range numbers all ranges highlight as expected, the format matches the example, this is about as simple as it gets, can anyone please explain why it isn't working?