We are currently running a campaign which allows leads to fill out a form to receive information on their preferred study option. I've noticed that 10 leads have filled out the form twice, but haven't changed their study option preference so have basically submitted the exact same form values twice. This doesn't always happen in quick succession - 7 of the 10 re-submitted hours or even days apart, and 3 leads submitted the same form within the same minute. One lead also had three separate form fills days apart with the exact same lead values for a completely different campaign.
I don't think there is a bot at play here, as I have checked each of the submissions and they are all from the same IP address and user agent. They are all from mobile though, so I'm wondering whether it's possible that the forms have have inadvertently been re-submitted somehow at a later date from the same mobile browser? The landing page redirects to a thank you page on submission, so I'm not sure how that would even be possible but it's the only thing I can think of.
I would love to limit the number of times leads can pass through the campaign, but I can't. There are genuine cases where leads will submit the form more than once with different lead values.
The only other possible reason for this is just actual, weird behaviour: people resubmitting pre-filled forms with exactly the same values because they feel like it.
Has anybody else experienced something similar?