Drag & Drop assistance

The Attempts field is set to 1, so the program doesn't allow re-submitting after the 1st attempt.

When you adjust Attempts to >1, SL automatically adds a Try Again layer, and it will allow only the designated number of attempts. 

Another issue: you renamed (or created from scratch) what should be the built-in Correct, Incorrect, and Try Again layers. It's best to keep those default layers, because the Submit trigger includes functionality to show them, as per what's set up in the question Design. 

Here's more info that you might find useful:

PRIMER: Graded Questions that Allow Multiple Attempts | Articulate - Community

Top 10 Tips for New Storyline Users | Articulate - Community 

Webinars, Primers, and Tips—Oh My! | Articulate - Community