Sounds like you are trying to use the shortcode directly on a page or post, rather than inside the Formidable Form’s On Submit Message Box.
Where is the shortcode? Use this form to provide a screenshot of where the shortcode is located. If the shortcode is NOT inside the On Submit Message Box, then you’ll need to place the shortcode inside a Formidable View and then add the view to the page or post.
Optionally, we can log in to take a look at your setup if you complete this form.
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