Adding Let's Encrypt SSL Certificate from Security tab did not work

I added a Let’s Encrypt SSL through the security tab but from what I can tell, the server doesn’t seem like it’s open to communication on port 443.

I did:

sudo apache2ctl -S

this was the response:

AH00558: apache2: Could not reliably determine the server’s fully qualified domain name, using 127.0.1.1. Set the ‘ServerName’ directive globally to suppress this message VirtualHost configuration: *:80 uptownecafe.com (/etc/apache2/sites-enabled/000-default.conf:4) ServerRoot: “/etc/apache2” Main DocumentRoot: “/var/www/html” Main ErrorLog: “/var/log/apache2/error.log” Mutex watchdog-callback: using_defaults Mutex rewrite-map: using_defaults Mutex default: dir=“/var/run/apache2/” mechanism=default Mutex mpm-accept: using_defaults PidFile: “/var/run/apache2/apache2.pid” Define: DUMP_VHOSTS Define: DUMP_RUN_CFG User: name=“www-data” id=33 Group: name=“www-data” id=33

the non https version of the site works fine. but need SSL for ecommerce.

please advise. thank you!