Cannont login, and I need to get in

Nextcloud version 19.0.0.12:
Operating system and version Ubuntu Server 20.04:
Apache or nginx version Apache/2.4.41 (Ubuntu):
PHP version PHP 7.4.7:

The issue you are facing:
Cannot login,

Is this the first time you’ve seen this error? (Y/N): Y

Steps to replicate it:

  1. try to login to https://cloud.sturtz.ml

The output of your Nextcloud log in Admin > Logging:
Last line:

{"reqId":"aAWdjsXMpVu9ayKrUrJ9","level":3,"time":"2020-07-07T14:12:26+00:00","remoteAddr":"192.168.1.6","user":"nsturtz","app":"PHP","method":"GET","url":"/index.php/core/apps/recommended","message":"You are using a fallback implementation of the intl extension. Installing the native one is highly recommended instead. at /var/www/nextcloud/3rdparty/patchwork/utf8/src/Patchwork/Utf8/Bootup/intl.php#18","userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.116 Safari/537.36","version":"19.0.0.12"}

full text, here
https://team.sturtz.ml/nextcloud.log

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

<?php
$CONFIG = array (
  'instanceid' => 'oc5xsicc1n42',
  'passwordsalt' => 'XgeOfxgDHhVGIUSD8vumLbFphaVND2',
  'secret' => '2D+JvtJZrEjTbVYDS/165m2ormI6yLrus0X9/w0bkFxc879z',
  'trusted_domains' => 
  array (
    0 => 'cloud.sturtz.ml',
  ),
  'datadirectory' => '/var/data',
  'dbtype' => 'mysql',
  'version' => '19.0.0.12',
  'overwrite.cli.url' => 'https://cloud.sturtz.ml/app',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'username',
  'dbpassword' => 'password',
  'installed' => true,
  'mail_smtpmode' => 'smtp',
  'mail_smtpsecure' => 'ssl',
  'mail_sendmailmode' => 'smtp',
  'mail_from_address' => 'no.reply',
  'mail_domain' => 'sturtz.ml',
  'mail_smtpauth' => 1,
  'mail_smtphost' => 'smtp.yandex.ru',
  'mail_smtpport' => '465',
  'mail_smtpname' => 'no.reply@sturtz.ml',
  'mail_smtppassword' => 'Purpl3&G0lD',
  'htaccess.RewriteBase' => '/',
  'app_install_overwrite' => 
  array (
    0 => 'registration',
    1 => 'twofactor_email',
    2 => 'socialsharing_email',
    3 => 'dashboardcharts',
    4 => 'admin_notifications',
    5 => 'socialsharing_twitter',
    6 => 'dashboard',
    7 => 'socialsharing_facebook',
    8 => 'issuetemplate',
  ),
  'twofactor_enforced' => 'true',
  'twofactor_enforced_groups' => 
  array (
    0 => 'admin',
  ),
  'twofactor_enforced_excluded_groups' => 
  array (
    0 => 'Family',
  ),
);

The output of your Apache/nginx/system log in /var/log/apache2:

[Wed Jul 08 00:00:01.666064 2020] [mpm_prefork:notice] [pid 965] AH00163: Apache/2.4.41 (Ubuntu) PHP/7.4.7 OpenSSL/1.1.1f configured -- resuming normal operations
[Wed Jul 08 00:00:01.666111 2020] [core:notice] [pid 965] AH00094: Command line: '/usr/sbin/apache2'
[Wed Jul 08 14:00:09.268821 2020] [access_compat:error] [pid 19797] [client 192.168.1.7:49487] AH01797: client denied by server configuration: /var/www/nextcloud/config

I got in, can someone tell me why I could not login?

No real idea.

Perhaps install
apt-get get php-intl

I cannot tell if that is what was wrong, but thank you for your reply.

You still have the problem?

No, the issue resolved it’s self, I am now wondering why it happened?