Thank you for reaching out to Constant Contact API Developer Support. My team is here to assist outside software developers with questions about building into Constant Contact's API.
There haven't been any changes made to the /v3/emails endpoint, but if you're not receiving a response body when making a call to that endpoint with a valid token and receiving a 200 response, we're happy to take a look in our logs to see if we can pinpoint the cause of the issue.
If you still need assistance with this, could you please provide us with the API key that you are using to make the request, the full request(s) where you are receiving the response (including URL, headers, timestamp, and request body), the full response body, and the username of the account that you are making the call to so that we can so that we can better assist you in identifying the root cause of the issue?
Please do not post the requested information in reply to this forum, as it may contain sensitive information. Instead:
Please email the requested information to our team at webservices@constant contact.com and reference case #30442453.
Please have a look and let us know if you have any other questions!
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