Many of the responses from individuals are duplicates

Many of the responses from individuals are duplicates. They are identical, but were submitted at slightly different times. Why is this - and how can it be prevented?

Thanks

Is the issue related to your "Complete This Form To View Your Graduation Photos!" form?

How many times did this happen? Can you provide us the IDs of duplicate submissions?

Where to Find the Submission ID?

What is the timeframe between duplicate submissions? If the time frame is just a few seconds, maybe there was an issue on your end or the users clicked multiple times on the submit button. If the timeframe is several minutes, hours or even days, most likely the users did not close the Thank You page and they reloaded it, which triggered another submission. 

Duplicate submissions can be prevented with the following features:

How to Set Unique Submissions on a Form

How to set Form Limits Based on a Unique Question

I tested your form and it was submitted only once. If the form is embedded, please provide us a webpage URL and we will test it there. In case that the issue is related to some other form, please provide us a form URL.