Hi Im using Oauth2.0 and I am getting redirect_uri_mismatch error. However I've checked the URI and the redirect_uri I send to https://oauth2.constantcontact.com/oauth2/oauth/token is the same as what I've registered with for the API key. I found another example of uri_mismatch : another redirect_uri issue . However the OP suggested that he needed to attach the API key to the redirect_uri. Do you know how this is done or where this is documented.
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