Hey Val,
I fixed it over the weekend. It was weird. I found a similar dropdown on a "read only" page I made so I knew the process still worked. I'm just not sure why it stopped on my other screens.
Basically, I added a generic dropdown to the screen and then copied all the "text change" processes from the original dropdown over to the generic one.
Then I removed the Customer dropdown that didn't work. Saved. Closed.
I logged back in, went to the screen, and added the "customer dropdown" back to the screen. copied over the "text change" processes from the generic one and deleted the generic one. Saved. Tested.
It worked. Not sure what happened but it works now.
:)