Can you try following again the instructions in the article you linked (this one: https://docs.bitnami.com/aws/faq/get-started/access-phpmyadmin/). Watch the video as well to be sure you are not missing any step.
To check that there are not weird redirections, can you run this from your Ubuntu machine in AWS?
$ curl -IL http://127.0.0.1/phpmyadmin/
On the other hand, if what you want is to access PhpMyAdmin without having to use a tunnel, you will have to modify the
If you want to allow access from only your IP, change this line:
to this one:
You can get your IP at http://myip.bitnami.com/
If, on the other hand, you want to allow access from any IP, just remove these two lines:
After your changes are saved, restart the server.