SSH into the machine, and run the bncert tool:
Follow prompts to set your domains and request certificates, as part of this process it will also set the server name to your domain, allowing you to access website via domain.
If you don't want to set up domain yet, run the below command, replace NEW_DOMAIN with your IP address:
sudo /opt/bitnami/apps/magento/bnconfig --machine_hostname NEW_DOMAIN
This tells magento that your current IP address is the server name and should respond accordingly when accessed in browser.