Can't launch socket under another domain on the same server - apache

Question

So far, I've got a funny problem. I had a socket running on my server for months, and I've came up with an idea of changing the host name.
After I did change the host name, and the links to the certificates, the socket no longer worked.
I own both domain names currently, let's say they are example-old.com and example.com, and I have certificates for both domains, issued by Cloudflare, both are wildcard ones (i.e., for example.com and *.example.com).
I didn't change the server, I didn't even restart it. When I change example back to example_old, both server name and certificate paths, everything works again. However, once I put the newer domain name here, nothing changes for it - socket.example.com just resolves as a 404 (as it would be even without virtual host declaration).
So, here's the code in /etc/apache2/sites-available/000-default.conf which declared my socket server.
<VirtualHost *:80>
ServerName socket.example.com
ServerAdmin webmaster#localhost
DocumentRoot /var/www/html
ProxyVia on
RewriteEngine on
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
<VirtualHost *:443>
DocumentRoot /var/www/html
ServerName socket.example.com
SSLEngine on
SSLCertificateFile /var/www/subdomains/example/example.pem
SSLCertificateKeyFile /var/www/subdomains/example/example.key
SSLCertificateChainFile /var/www/subdomains/example/example.pem
SSLProxyEngine On
ProxyPreserveHost On
ProxyRequests Off
# This is for websocket requests
ProxyPass /wss wss://localhost:9024/
ProxyPassReverse /wss wss://localhost:9024/
ProxyPass /wchat wss://localhost:9025/
ProxyPassReverse /wchat wss://localhost:9025/
ProxyPass / https://localhost:3333/
ProxyPassReverse / https://localhost:3333/
</VirtualHost>
I don't really remember if this change is the only one that has to be done in order for changing my socket server.
As a socket, I use Workerman for PHP. As neither the port, nor the server changed, I left my file socket.php untouched. When I launch the socket.php with the new domain names in /etc/apache2/sites-available/000-default.conf, everything is silent, it doesn't respond neither to new connections, nor to anything else.
I also experimented with leaving running socket under the old domain name, declaring the same virtual host for the new domain name and trying to launch another instance of socket. The one, running on the old domain, works perfectly, while the new doesn't.
What could I do wrong? As far as I understand, there're must be something else that I must have done months ago when launching the original socket server. However, I don't remember what was it.

Answer 1

I found the solution finally, if anyone is wondering
Switched flexible to full encryption on Cloudflare and everything started working