pivot table field settings product

I have created a spreadsheet - I have a pivot table completed showing dates in the values column by choosing the value field "product" under field settings.  I created a new pivot table using the same data so I could add a "add measure" column because I didn't know that option existed when I created the first pivot table.  NOW when I try add the date information I do not have a "product" option under the date field.  I have a "distinct count" which is different than the other pivot table options - but I need the "product" option to show the actual date.

What is happening? What am I doing wrong.  I am thrilled I can now show text in the values column by using the "add measure" but I need the date to show!