Same problem here. In V2 of the API We have a simple HTML/PHP signup form on a basic landing page We have an API key, a Secret, and a Token Users fills out the form, agrees to terms, gets a Double opt in Result: using the LIST_ID, and 2 custom fields the user is added to a specific list. done. (works great only in V2) that brings us to v3... :(. . . I think you are right, so far it has proven Impossible to accomplish the simple task of "adding 1 user to a specific list with some custom fields" No way to generate an access token that stays good long enough to leave the landing page up No way to add 1 user to a specific list Documentation does not make sense Constantly have to refresh the token No clear examples Examples given do not work Other problems we ran into: https://v3.developer.constantcontact.com/api_guide/contacts_create.html Create contacts has no explanation on how to add that 1 user to a specific list 'authorization' => 'Bearer {access_token}' Disambiguation needed Assume access_token = 12345 Does not work: '{12345}' Does not work: 'Bearer {12345}' Does not work: 'Bearer 12345' Does not work: '12345' access_token and refresh_token constantly expire Impossible to hardcode API_key, Secret, Token into a variable in PHP to allow landing pages to work Our Conclusion: V3 does not work for adding 1 contact to a list after they fill out a form. Ergo: Our solution was and still is to use v2 (or switch to another platform that has a working API, which seems rude/inappropriate to talk about any further in this forum) Sorry... but you are not alone!
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