Getting Duplicate Entries

Hello,

I have the same issue as described at https://wordpress.org/support/topic/getting-duplicate-entries/

We run WordPress on http://www.vcas-os.cz. At https://www.vcas-os.cz/online-prihlaska-lt2019/ we run a registration form that uses the official WordPress plugin Formidable (without modification) to submit for each submitted application:

* saves form content into the Formidable plugin database
* sends an e-mail with a recap of the application to the legal guardian and to the two notices of our association

Unfortunately, the same applications are repeatedly sent, even several times in succession, irregularly even at intervals of several days. For some duplicates, the IP address remains the same.

Interesting fact is that during the registration period we add one new field to the form so client who did the registration before the change submitted form without the field and clients who did the registration after the change submitted form including the new field. And there is an entry which was initially submited before the change (without the new field) and the duplicite of the entry was created after the change – but still without the new field. Such a setup is not possible to be executed with the new submitting of the form as the new submitting would contain the new field.

It seems that the duplicites appear as the re-execution of the old entries cached somewhere.

I definitely do not use API form features so the suggested solution that “it sounds like someone is clicking the link to duplicate an entry” (mentioned at https://wordpress.org/support/topic/getting-duplicate-entries/) seems unreal for my case.

Kind regards

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