In a Pivot Table the formula will convert to the column heading names.
If Column "C" has the heading: Column1
And Column "D" has the heading: Column2
If the place that you put the formula is up against the table, it will become part of the table.
And the formula will look like this:
=IF(AND([@Column1]=1,[@Column2]=0),"closed","still open")
If the formula is not apart of the table then it has to reference the table;
Lets say the Table is named: Table4
Then it will look like this;
=IF(AND(Table4[@Column1]=1,Table4[@Column2]=0),"closed","still open")