Hi! Yes, even if I got this error saving something inside mailchimp, you are right, the problem is inside duplicate-post. Thanks a lot for the answer 🙂
Hi,
Same error here, including same time working (4 years). Yesterday I was creating a new form and figure out that all forms are not working anymore. I do not get any error message when I submit an e-mail.
To: Gmail account
From: email from same website domain
Plugin version: 5.3
Regards
Tatiane
