get apache2 to listen to several ports

Question

I am trying to make different applications in different ports, my /var/www/ directory contains two directories : FlaskApp and html .

I want to make FlaskApp work on port 81 and html to work on 80

In etc/apache2/ports.conf I have this:

Listen 80

<IfModule ssl_module>
        Listen 443
</IfModule>

<IfModule mod_gnutls.c>
        Listen 443
</IfModule>

Listen 81

In /etc/apache2/sites-enabled/FlaskApp.conf I have this:

<VirtualHost *:81>
                ServerName feniksgaming4987.cloudapp.net
            
                WSGIScriptAlias / /var/www/FlaskApp/flaskapp.wsgi
                <Directory /var/www/FlaskApp/FlaskApp/>
                        Order allow,deny
                        Allow from all
                </Directory>
                Alias /static /var/www/FlaskApp/FlaskApp/static
                <Directory /var/www/FlaskApp/FlaskApp/static/>
                        Order allow,deny
                        Allow from all
                </Directory>
                ErrorLog ${APACHE_LOG_DIR}/error.log
                LogLevel warn
                CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>

When I change to FlaskApp works but I can't access html directory.

Please any help... I tried everything in here but nothing works.