Contact Form 7 redirect to 404 not found page when creating a new form.

Hi,

When I try to make a new form ( or even duplicate the standard and save with new name ) I got redirected to a 404 not found page and the link looks like this:

https://nationwidethailand.com/wp-admin/admin.php?page=wpcf7&post=20814

I have tried to uninstall and reinstall the Contact Form 7 plugin, and also deactivated all the other plugins installed.

Also there is no errors on javascripts when debugging.

I see some other user experience the same problem but I can not find any solution out there.

Hope someone can answer this.

Thanks,

Marius

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