Use PUT to insert or update list members.

Hello
I’m having some issues using the plugin.
It works ok but I get the following error:

Mailchimp Error
Error while creating e5dc7af59a (-@GMAIL.COM is already a list member. Use PUT to insert or update list members.)

I’ve selected the option to update contact if it’s already in list but i’m still getting this email.

Any idea of what can be causing it or how to fix it?
Thank you

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