Unable to suppress columns in Smart View retrieve

Summary:

Apologies if this is the wrong forum on which to ask this - I have created a Smart View retrieve to extract data from ERP, however in Smart View -> Options -> Data Options it will only allow me to Suppress Rows but not Suppress Columns (the options for column suppression are greyed out). Why is this? Is this something to do with the way I have created / structured this retrieve?

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