In call to Function SortIndex, the first parameter, «D», is missing, but is not optional. In call to Function Unique, the second parameter, «I», is missing, but is not optional.
This is a lexical error -- meaning it is detected when parsing an expression (as opposed to an evaluation error, which is detected while evaluating an expression).
You've entered a call to the indicated function, but have omitted a required parameter.
Specify the missing parameter.
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