Why am I getting duplicate orders?

I am using JotForm to register students for training classes.  I have also integrated the Auth.net add-on into the form so students can purchase the class at the same time they register.  Over the past few weeks we have been getting at least 1-2 "duplicate" orders per day.  There are other orders that are not duplicates but then some are.  In the duplicate orders, the form information is identical but the Authorize.net transaction ID and codes are different. 

HELP!

Josh

The submissions look to be legitimate entries.  It is very likely the users submitted the form, pressed back on their browsers, then submitted the form again with the same data.  If the submissions were duplicating on our end, the time stamps would be nearly identical and it would be consistent.

Thanks for the quick reply!  

Ok, thats kinda what I was thinking. What should I do? 

http://www.procprclasses.com/checkout-cpr/

This form also has duplicate orders.  Can you check this one?

The same will be true for your second form.  Duplicate entries do not happen unless the form is actually submitted twice. 

If students should only be able to register once, you can set up unique submissions to prevent duplicates:

http://www.jotform.com/help/64-How-to-Set-Unique-Submissions-on-a-Form

As for the payments, you would need deal with the extras through Authorize.net. 

Ok, I will look into the unique submissions.  

Should I also put something in the completed order message stating not the "press the back button"?

Thanks again for your help

Generally, when people get to the thank you page, they tend not to return to the form and submit it again.  If you are using the default thank you page though, it could be vague as to whether or not payment was received.  I always like to err on the side of letting users know as much as possible.  Letting them know their payment was received and that returning to the form and submitting it again will charge them again would probably cut down on duplicates.

Ok, sounds good.  I'll give it a try and hopefully this will work. Thank you!