Apache2 Reverse Proxy HTTPS Error During SSL Handshake

Question

I am setting up Apache2 as a "gateway" inside a private network. I am trying to forward HTTPS Traffic from outside through internal network with apache2.

I got it to work with HTTP but as soon as I switched to HTTPS it doesnt work anymore.

The error that I get is:

[Tue May 02 14:52:51.347146 2023] [proxy:error] [pid 5423:tid 140612283090496] [client my.ip:17059] AH00898: Error during SSL Handshake with remote server returned by /
[Tue May 02 14:52:51.347161 2023] [proxy_http:error] [pid 5423:tid 140612283090496] [client my.ip:17059] AH01097: pass request body failed to 100.100.100.100:553 (100.100.100.100) from 100.100.100.100 ()
[Tue May 02 14:52:51.397245 2023] [proxy:error] [pid 5423:tid 140612145747520] [client my.ip:17060] AH00898: DNS lookup failure for: 100.100.100.100:553favicon.ico returned by /favicon.ico, referer: https://example.com:2230/

My Config looks like this:

<VirtualHost *:2230>
        ServerName example.com
        ErrorLog ${APACHE_LOG_DIR}/proxy/error.log
        CustomLog ${APACHE_LOG_DIR}/proxy/access.log combined

         <Proxy *>
        Order deny,allow
        Allow from all
        Authtype Basic
        Authname "Password Required"
        AuthUserFile /etc/apache2/passwords
        Require valid-user
        </Proxy>

        SSLEngine on
        SSLProxyEngine on
        SSLProxyVerify none
        SSLProxyCheckPeerCN off
        SSLProxyCheckPeerName off
        SSLProxyProtocol +TLSv1
        SSLCertificateFile /etc/letsencrypt/live/example.com/fullchain.pem
        SSLCertificateKeyFile /etc/letsencrypt/live/example.com/privkey.pem
        Include /etc/letsencrypt/options-ssl-apache.conf


        ProxyPreserveHost On
        ProxyPass / https://100.100.100.100:553
        ProxyPassReverse / https://100.100.100.100:553
</VirtualHost>

Does someone have an ideea which can be the issue?