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We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
The issue is being caused by the theme applied to your form.
Please change the theme to the Default in your Preference settings:
This will remove the line from within your form. You can see the change in the clone version of your form here: http://support.jotform.com/form/52273764455966?
Please inform us if you need further assistance.