Newbie problem:

I have 3 combo-boxes and two text boxes:

cmbCode cmbActivity cmbPOC (order by priority level)
txtEmail txtPhone

Right now I can select any cmb and get a full list from my tables. If I select cmbCode>>cmbActivity is limited to Activitys aligned with that Code
AND if I select a Activity from cmbActivity>>cmbPOC is limited to POCs aligned with that Activity and it displays that POC's Email and Phone in txtEmail and txtPhone per POCs

What I want: to be able to change the cmbActivity selection and have the drop down list in cmbActivity requery to the new Activity
I do not want the POC or txtEmail or txtPhone to change its content unless user actually selects something from the newly requeried list

I hope this makes sense. Thank you for your help!!!