我多次检查了所有配置。一切似乎都很好。

sudo apache2ctl configtest

Syntax OK

apache2ctl -S

VirtualHost configuration:
*:80                   is a NameVirtualHost
         default server XX.leaseweb.net (/etc/apache2/sites-enabled/000-default.conf:1)
         port 80 namevhost XX.leaseweb.net (/etc/apache2/sites-enabled/000-default.conf:1)
         port 80 namevhost XX0.ch (/etc/apache2/sites-enabled/XX0.ch.conf:1)
                 alias www.XX0.ch
         port 80 namevhost XXloud.com (/etc/apache2/sites-enabled/XXloud.com.conf:1)
                 alias www.XXloud.com
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

所有文件均使用chown www-data设置：www-data
权限设置：

sudo chmod -R 755 /var/www

/etc/apache2/sites-available/XX0.ch.conf

<VirtualHost *:80>
    ServerAdmin webmaster@XXloud.com
    ServerName XXloud.com
    ServerAlias www.XXloud.com
    DocumentRoot /var/www/XX0.ch
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
RewriteEngine on
RewriteCond %{SERVER_NAME} =XXloud.com [OR]
RewriteCond %{SERVER_NAME} =www.XXloud.com
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,NE,R=permanent]
</VirtualHost>

<IfModule mod_ssl.c>
<VirtualHost *:443>
    Protocols h2 h2c http/1.1
    ServerAdmin webmaster@XXloud.com
    ServerName XXloud.com
    ServerAlias www.XXloud.com
    DocumentRoot /var/www/XX0.ch
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
    <IfModule mod_headers.c>
      Header always set Strict-Transport-Security "max-age=15552000; includeSubDomains"
    </IfModule>
Include /etc/letsencrypt/options-ssl-apache.conf
SSLCertificateFile /etc/letsencrypt/live/XX0.ch/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/XX0.ch/privkey.pem
</VirtualHost>
</IfModule>

通过phpinfo（）在站点上调用服务器的IP地址可以工作！

//http://XXX.XXX.62.175/index.php

phpinfo();
=> Shows correctly PHP Version 8.2.6

重新启动Apache时没有错误。在更新之前，一切正常。包括SSL/TSL调用。
有人有解决办法吗？