Backup failed

Hello, every time I want to create a backup, no matter whether to FTP, directory or Dropbox, it stops after 10 seconds.
The information says the following:
WordPress-Version: 5.3.2
BackWPup-Version: 3.7.0
PHP-Version: 7.3.14 (64bit)
MySQL-Version: 5.7.28-log
cURL-Version: 7.38.0
cURL-SSL-Version: OpenSSL/1.0.1t
WP-Cron-URL: https://mrs-greenery.de/wp-cron.php
Server-Selbstverbindung: Nicht erwartete HTTP-Antwort:
Status-Code: 403
Content-type: text/html; charset=UTF-8
Date: Fri, 31 Jan 2020 10:31:34 GMT
Server: Apache
X-powered-by: PHP/7.3.14
Content-encoding: gzip
Inhalt: Access denied.

Document root: /kunden/homepages/20/d812866477/htdocs/mrs-greenery
Temp-Verzeichnis: /homepages/20/d812866477/htdocs/mrs-greenery/wp-content/uploads/backwpup-ad18aa-temp/
Protokoll-Verzeichnis: /homepages/20/d812866477/htdocs/mrs-greenery/wp-content/uploads/backwpup-ad18aa-logs/
Server: Apache
Betriebssystem: Linux
PHP-SAPI: cgi-fcgi
Aktueller PHP-User: u99700016
Maximale Skript-Laufzeit: 50000 Sekunden
BackWPup Maximale Script-Ausführungszeit: 0 Sekunden
Alternative WP Cron: Aus
WP Cron abgeschaltet: Aus
Verzeichnis-Rechte: 493
Server-Zeit: 10:31
Zeit der Website: 11:31
Zeitzone der Website: Europe/Berlin
Zeitverschiebung der Website: 1 Stunden
Sprache der Website: de-DE
Zeichensatz des MySQL-Clients: utf8
PHP-Memory-Limit: -1
WordPress-Memory-Limit: 40M
Maximales WordPress-Memory-Limit: -1
Benutzter Speicher: 83,00 MB
Geladene PHP-Erweiterungen:: Core, PDO, Phar, Reflection, SPL, SimpleXML, bcmath, bz2, calendar, cgi-fcgi, ctype, curl, date, dba, dom, exif, fileinfo, filter, ftp, gd, gettext, gmp, hash, iconv, imap, intl, json, libxml, mbstring, mysqli, mysqlnd, openssl, pcre, pdo_mysql, pdo_sqlite, posix, session, shmop, soap, sodium, sqlite3, standard, tidy, tokenizer, wddx, xml, xmlreader, xmlwriter, xsl, zip, zlib

I tried to ad wp-cron in wp-config.php but then I get the message: access denied.
Thanks for your help!

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