Post tags not populating

I added Post Tags field to one of my forms that will populate a custom post. I renamed the field of the Post Tags to "Publisher" and choose "Drop Down" as my field type. Unfortunately, while the form is collecting the data, it is not populating the tag field.

Here is a link to my form: form

I think I am using Custom Post Types (although I don't know if that is accurate). I checked "Create Post content template" but it feeds to the main Post admin page.