Image upload not possivble on WordPress

When I try to upload an image (both small or big) to the WordPress Media, I get the following error message:

“Die Verarbeitung des Bildes ist fehlgeschlagen. Der Server ist m?glicherweise ausgelastet oder hat nicht genügend Ressourcen zur Verfügung. Eventuell hilft es, wenn du ein kleines Bild hochl?dst. Die vorgeschlagene Maximalgr??e ist 2500 Pixel.”

In English translates to something like:
“Image processing has failed. The server may be busy or may not have enough resources available. It might help if you upload a small image. The suggested maximum size is 2500 pixels.”

Strangely enough, the images show up after reloading, but when I try to insert them into a page or post, it does not work and I get a 503 error.

Would greatly appreciate any help with this issue!

Here the Health report from my site:

### wp-core ###

version: 5.5.3
site_language: de_DE
user_language: de_DE
permalink: /%postname%/
https_status: true
user_registration: 0
default_comment_status: open
multisite: false
user_count: 6
dotorg_communication: true

### wp-paths-sizes ###

wordpress_path: /html/begeisterungsland.de/public
wordpress_size: 100,00 MB (104856608 bytes)
uploads_path: /html/begeisterungsland.de/public/wp-content/uploads
uploads_size: 1,62 GB (1741026256 bytes)
themes_path: /html/begeisterungsland.de/public/wp-content/themes
themes_size: 58,32 MB (61155428 bytes)
plugins_path: /html/begeisterungsland.de/public/wp-content/plugins
plugins_size: 191,51 MB (200812963 bytes)
database_size: 53,16 MB (55741440 bytes)
total_size: 2,02 GB (2163592695 bytes)

### wp-dropins (1) ###

advanced-cache.php: true

### wp-active-theme ###

name: Infinite (infinite)
version: 3.3.4
author: Goodlayers
author_website: https://www.goodlayers.com
parent_theme: none
theme_features: core-block-patterns, automatic-feed-links, title-tag, editor-style, menus, post-thumbnails, post-formats, html5, woocommerce, wc-product-gallery-zoom, wc-product-gallery-lightbox, wc-product-gallery-slider, widgets
theme_path: /html/begeisterungsland.de/public/wp-content/themes/infinite

### wp-themes-inactive (1) ###

Twenty Twenty: version: 1.5, author: WordPress-Team

### wp-mu-plugins (2) ###

Asset CleanUp Pro: Plugin Filtering: version: 1.0, author: Gabriel Livan
Health Check Troubleshooting Mode: author: (undefined), version: 1.7.2

### wp-plugins-active (32) ###

Advanced Editor Tools (previously TinyMCE Advanced): version: 5.5.1, author: Automattic
Asset CleanUp Pro: Page Speed Booster: version: 1.1.8.3, author: Gabriel Livan
Breadcrumb NavXT: version: 6.6.0, author: John Havlik
Classic Editor: version: 1.6, author: WordPress Contributors
Cookie Notice: version: 1.3.2, author: dFactory
Goodlayers Core: version: 1.3.8, author: Goodlayers
Goodlayers Personnel Post Type: version: 1.1.9, author: Goodlayers
Goodlayers Portfolio Post Type: version: 1.2.5, author: Goodlayers
Google Analytics for WordPress by MonsterInsights: version: 7.13.2, author: MonsterInsights
Google Tag Manager for WordPress: version: 1.11.6, author: Thomas Geiger
Health Check & Troubleshooting: version: 1.4.5, author: The www.remarpro.com community
Loco Translate: version: 2.4.6, author: Tim Whitlock
LuckyWP Table of Contents: version: 2.1.4, author: LuckyWP
Newsletter, SMTP, Email marketing and Subscribe forms by Sendinblue: version: 3.1.0, author: Sendinblue
Newsletter2Go: version: 4.0.12, author: Newsletter2Go
Podcast Subscribe Buttons: version: 1.2.7, author: SecondLine Themes
Quiz And Survey Master: version: 7.1.8, author: ExpressTech
Read More: version: 2.6.3, author: Edmon
Redirection: version: 4.9.2, author: John Godley
Schema & Structured Data for WP & AMP: version: 1.9.56, author: Magazine3
Seriously Simple Podcasting: version: 2.4.2, author: Castos
Seriously Simple Stats: version: 1.2.9, author: Castos
Shield Security: version: 10.1.3, author: Shield Security
Smush: version: 3.7.3, author: WPMU DEV
Sticky Menu (or Anything!) on Scroll: version: 2.25, author: WebFactory Ltd
Thrive Architect: version: 2.6.3, author: Thrive Themes
Thrive Leads: version: 2.3.5, author: Thrive Themes
Thrive Product Manager: version: 1.2.4, author: Thrive Themes
UpdraftPlus – Backup/Restore: version: 1.16.40, author: UpdraftPlus.Com, DavidAnderson
WP Mail SMTP: version: 2.5.1, author: WPForms
WP Rocket: version: 3.7.5, author: WP Media
Yoast SEO: version: 15.3, author: Team Yoast

### wp-plugins-inactive (1) ###

AudioTyped UX: version: 1.0.21, author: Helmut Naber, AudioTyped

### wp-media ###

image_editor: WP_Image_Editor_Imagick
imagick_module_version: 1690
imagemagick_version: ImageMagick 6.9.10-14 Q16 x86_64 20181023 https://imagemagick.org
imagick_limits:
imagick::RESOURCETYPE_AREA: 26 GB
imagick::RESOURCETYPE_DISK: 1.844674407371E+19
imagick::RESOURCETYPE_FILE: 768
imagick::RESOURCETYPE_MAP: 26 GB
imagick::RESOURCETYPE_MEMORY: 13 GB
imagick::RESOURCETYPE_THREAD: 8
gd_version: bundled (2.1.0 compatible)
ghostscript_version: not available

### wp-server ###

server_architecture: Linux 4.19.44-gentoo-mw1 x86_64
httpd_software: Apache
php_version: 7.4.1 64bit
php_sapi: fpm-fcgi
max_input_variables: 1500
time_limit: 240
memory_limit: 256M
max_input_time: 240
upload_max_size: 32M
php_post_max_size: 32M
curl_version: 7.64.0 OpenSSL/1.1.1b
suhosin: false
imagick_availability: true
server-headers:
date: Thu, 26 Nov 2020 09:39:22 GMT
server: Apache
expires: Wed, 11 Jan 1984 05:00:00 GMT
cache-control: no-cache, must-revalidate, max-age=0
referrer-policy: unsafe-url
x-frame-options: SAMEORIGIN
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
x-pingback: https://begeisterungsland.de/xmlrpc.php
upgrade: h2,h2c
vary: Accept-Encoding
content-encoding: gzip
content-length: 24929
content-type: text/html; charset=UTF-8
htaccess_extra_rules: true

### wp-database ###

extension: mysqli
server_version: 5.7.25-28
client_version: mysqlnd 7.4.1

### wp-constants ###

WP_HOME: undefined
WP_SITEURL: undefined
WP_CONTENT_DIR: /html/begeisterungsland.de/public/wp-content
WP_PLUGIN_DIR: /html/begeisterungsland.de/public/wp-content/plugins
WP_MAX_MEMORY_LIMIT: 256M
WP_DEBUG: false
WP_DEBUG_DISPLAY: true
WP_DEBUG_LOG: false
SCRIPT_DEBUG: false
WP_CACHE: true
CONCATENATE_SCRIPTS: undefined
COMPRESS_SCRIPTS: undefined
COMPRESS_CSS: undefined
WP_LOCAL_DEV: undefined

### wp-filesystem ###

wordpress: writable
wp-content: writable
uploads: writable
plugins: writable
themes: writable
mu-plugins: writable

### luckywp-table-of-contents ###

domVersion: 20031129
libxmlVersion: 2.9.4
intlVersion: 7.4.1
icuVersion: 63.1
settings: {“lwptoc_general”:{“min”:”3″,”depth”:”3″,”hierarchical”:true,”numeration”:”none”,”numerationSuffix”:”none”,”title”:”Inhaltsverzeichnis”,”toggle”:false,”labelShow”:”Anzeigen”,”labelHide”:”Verbergen”,”hideItems”:false,”smoothScroll”:true,”smoothScrollOffset”:”24″},”lwptoc_appearance”:{“width”:”full”,”float”:”none”,”titleFontSize”:”150%”,”titleFontWeight”:”bold”,”itemsFontSize”:”100%”,”colorScheme”:”light”,”backgroundColor”:null,”borderColor”:”#f0822b”,”titleColor”:”#1c1c1c”,”linkColor”:”#1122cc”,”hoverLinkColor”:null,”visitedLinkColor”:null},”lwptoc_autoInsert”:{“enable”:true,”position”:”beforefirstheading”,”postTypes”:[“post”]},”lwptoc_processingHeadings”:{“postTypes”:null},”lwptoc_misc”:{“skipHeadingLevel”:””,”skipHeadingText”:””,”hashFormat”:”asheading”,”hashConvertToLowercase”:false,”hashReplaceUnderlinesToDashes”:false,”wrapNoindex”:true,”useNofollow”:true,”showMetaboxPostTypes”:””,”listMarkupTags”:”div”,”containerClass”:null}}

### wp_mail_smtp ###

version: 2.5.1
license_key_type: lite
debug: Keine Debug-Hinweise gefunden.
db_tables: wp_wpmailsmtp_tasks_meta
lite_install_date: Okt 19, 2020 @ 8:58pm

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