I am experiencing an issue with one of my cascading drop downs.  I've created several of these over the last few years and one that I am currently working on is not responding.  I have attached 2 Word Documents to demonstrate the flow of 1 Cascading Drop Down that works perfectly, and one that is not functioning.

The file labeled "Eng Type Sub-Eng Type Lookup Flow" contains screenshots of the Cascading Drop Down that is functional.  The file labeled "Service Area Zip Code Lookup Flow" contains screenshots of the Cascading Drop Down that is not functional.

What I am trying to do with the one that is currently non-functional is allow my end users to select a Zip Code out of the Zip Code down, and the result make the corresponding Service Area in the Service Area drop down the only selectable option.

In the "Eng Type Sub-Eng Type Lookup Flow", I was successful in making to so that the Engagement Type drop down triggers specific selections in the Sub-Engagement Type column.

I'm not seeing what detail I may have done differently in the "Service Area Zip Code Lookup Flow" to make it not function.  Any assistance or insights on how to solve this issue would be greatly appreciated.  I'd like to add that I'm developing this form in a test environment, so there's no chance I'll negatively impact my production environment.  Thank you in advance!