Receiving the same error:
Mailchimp returned the following error:
Unauthorized. API Key Invalid. Your API key may be invalid, or you’ve attempted to access the wrong datacenter. Request: GET https://us19.api.mailchimp.com/3.0/?fields=account_id Response: 401 Unauthorized – {“type”:”http://developer.mailchimp.com/documentation/mailchimp/guides/error-glossary/”,”title”:”API Key Invalid”,”status”:401,”detail”:”Your API key may be invalid, or you’ve attempted to access the wrong datacenter.”,”instance”:”187c69cf-9933-4db2-a2db-5c1c233adc46″}
Created new API Key and same issue.