Problem with form redirect

Hi i am working in a website that has WPML for multilingual. I have set up a different form and subscriber list for each language. The users are being redirected to a custom page when they subscribe, and this action is completed successfully in spanish form, but in english form, the subscriber is redirected to this url

/wp-admin/admin-post.php?action=mailpoet_subscription_form

And obviously they can’t complete the process because they aren’t logged in (and i don’t want them to be logged in too, just subscribe to the newsletter and be redirected to another static page)

Any ideas on what could be causing this issue? I checked all the settings and everythings seems fine

Thanks in advance

Jean