Thank you for reaching out to Constant Contact API Support.
Since this is a 3rd-party integration and not built or supported by Constant Contact directly, I'm limited in the scope in which I can help with any problems with it.
While I can't rule it out completely, we are not likely blocking your IP address. When trying to connect your account are you seeing any error messages? I'd be happy to help in any way I can, but I may need to more information about the response Memberpress is getting from our API when you try to connect.
Please email email@example.com with the Constant Contact username, the API Key and Access Token you are using, and the last day and time you tried to connect. We can do some digging on our end to try to identify any problems. Regards, David B. Tier II API Support Engineer
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