Expressions that yield variant data-type cannot be used to define calculated columns.

Hi sureshdam18,

I think you are try to use both number value and text value in one calculate column so power bi can't auto analysis data type of this calculated column.

Maybe you can try to use 0 to replace "" part to keep similar data type or modify the column type to text.

Column=
IF (
    AND ( [Completion Status] = "Open", [Status] = "MD Ops Review - Delete" ),
    Sheet1[NET_DAY],
    0
)

Regards,

Xiaoxin Sheng