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JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
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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.
I have gone ahead and checked on your form "Dog Registration", it has double submit button however when hit any of them works fine, in other words, I was not able to replicate the issue.
My best advise for you please clean you browser's cache. Inside this guide you will find a step by step how to do so: http://www.jotform.com/help/229-How-to-Clear-your-Form-Cache.
This guide is also helpful: http://www.jotform.com/help/269-How-to-view-Submissions.
I hope this information helps.