The API call to the endpoint https://api.cc.email/v3/contacts/sign_up_form returns "Email address is invalid" for many calls. Here are some example email addresses which look like valid but all been rejected as "invalid".
Â
[example addresses redacted by Constant Contact for privacy purposes]
Â
I found this article
https://community.constantcontact.com/t5/Developer-Support-ask-questions/v3-api-returns-Email-address-is-invalid-for-no-apparent-reason/m-p/370114#M12556
It looks like if you see emails having signed up to multiple constant contact accounts in a short time, you will block sign ups from these addresses.
In our application, people can sign up multiple mailing list, but they all belong to the same constant contact account.
Â
Can explain what caused these emails been rejected?
