Cloudwatch plugin error - timing out when attempting to connect

I am seeing the following error on my EC2 RHEL instance:

cloudwatch: Error in ListMetrics API call : RequestError: send request failed caused by: Post dial tcp XX.XXX.16.180:443: i/o timeout.

I can manually run a single telegraf collection and output metrics to stdout using command => telegraf --config telegraf.conf --test. Is there something I have to do to connect port 443? The telegraf service starts up fine and stays in a ‘running’ state but consistently shows the timeout errors above when attempting to connect to cloudwatch. I have configured AWS credentials in the ‘outputs.cloudwatch’ plugin section but it doesn’t even seem like I’m getting that far yet…since it appears not even to successfully connect.

Any ideas?
Thanks in advance!