First, remove the criteria (Between start date and end date" from the query to make sure it is returning something. If not you have lost its reference data. Recreate the query making sure to point it to the correct data source. If it does return ALL of you data then make sure the critieria "Between start date and end date" must be under the query field for the date.
If neither of these work post back with as much detail as you can and we'll try to work through it.
Autoeng