Please fill out the fields below so we can help you better. Note: you must provide your domain name to get help. Domain names for issued certificates are all made public in Certificate Transparency logs (e.g. https://crt.sh/?q=example.com), so withholding your domain name here does not increase secrecy, but only makes it harder for us to provide help.
The operating system my web server runs on is (include version): Ubuntu 16.04
My hosting provider, if applicable, is: Microsoft Azure
I can login to a root shell on my machine (yes or no, or I don’t know): Yes
I’m using a control panel to manage my site (no, or provide the name and version of the control panel): No
When I visit my site in Chrome, SSL works just fine. In Desktop Safari (mobile works fine), I get a ‘Connection Not Private’ warning. Why is this happening? How do I fix it? God, I hate SSL.
Your certificate isn't valid for www.enmtw.com, only for enmtw.com. Chrome has made a questionable decision to ignore this particular error, while other browsers don't. You can fix the problem by reissuing your certificate and making sure that it covers both names.
When I run certonly, I can enter both domains. When I run the Nginx command, I am only prompted with the enmtw.com domain, not the WWW variant. Not sure what the syntax is to tell Certbot ‘hey, let me punch in my domains’.