Logging for tracking problems on the form.

Hello,

Is there any source of logs or anything else that would tell me why a submitted form would return an error and require the user to start filling out the form again?

Unfortunately, there isn't such a log. Are you experiencing issues with the form after submitting? Can we try making a real submission in order to test the form?

Yes, they form is filled out and submit is clicked and then it resets the form and they are required to fill it out again.

Please try a test submission.  I think it will likely work fine for you and I expect the issue is actually with the user, their device, their internet...any number of things.  I just thought I'd ask to see if there was any way to trace it back and identify any problems.  Thanks.

You may also use the Form Analytics tool to review how your users uses the form.

Understanding Form Analytics and Ways on How to Get Your User's Info

and you can do this as well How to Catch User's Browser Info

I hope this help. Let us know if you need further assistance.