Empty Combo Box

Hey guys......simple problem
I have a form with 3 combo boxes.

The 1st combo, called winecode, gets the values from the following sql:
SELECT [winecode] FROM wine WHERE winedesable=0;
it works.....

The second combo box, called suppname, gets the values from another select, but depending on the previous combo:
SELECT DISTINCT [supplier].[suppname] FROM supplier, suppwine WHERE [supplier].[suppnumber]=[suppwine].[suppnumber] And [suppwine].[winecode]=[Forms]![addpop]![winecode];
it works......

The 3 rd combo, called winesubcat, gets the values from a query which takes the selected value from the previous 2 combos. The query works by it self . However, i added the query in the data tab and open the form. then i selected values from the first 2 combos and there is no value in the 3rd combo...... any idea??

thx max.