If this is happening in your website, I would suspect that it is possible that you are connected to the wrong Constant Contact account. In order to make sure you are connected to the correct account, I would double-check that your website is using the correct Access Token by re-entering it with the token that you get from Mashery's I/O Docs.
Please let me know if this does not resolve your issue.
Elijah G. API Support Engineer
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