Although this might not help the poster in this case,
I had a similar issue with an AWS Lightsail instance and just wanted to share my solution.
The problem for me was that the Lightsail instance did not have port 2030 open.
By default, the AWS Lightsail instances only have port 22 and 80 open. So you have to go to your instance in the lightsail control panel and click the networking tab and add port 2030 (I added it as 'Custom' over TCP).
(While you're at it, if you plan on using SSL(https) on your website/app then you need to open port 443 as well.)
Just thought I'd share!
Sometimes when you're doing something new (in my case CWP) it's easy to overlook even the most basic of settings because you mistakenly think there's something wrong with the new stuff! :>