What error message do you see?
This:
Hmm .. looks like you didn’t send any credentials.. No CSRF for you!
https://cloud.erstensmertens.de/index.php/s/5D9TCoYrMT8QFaT
What other plugins and theme do you use on the site?
Akismet Anti-Spam 4.2.1
Change font size and color 1.0.0
Classic Editor 1.6.2
Contact Form 7 5.4.2
GDPR Cookie Compliance (CCPA, PIPEDA ready) 4.5.11
Ninja Forms 3.6.0
Site Kit by Google 1.42.0
Theme Editor 2.6
The SEO Framework 4.1.5.1
W3 Total Cache 2.1.8
WordPress Importer 0.7
WP Accessibility 1.7.9
WPForms Lite 1.7.0
—-
Avada 6.1.0
Accelerate 1.5.0
Flash 1.4.3
Grocery Store 1.0.9
Nirvana 1.6.1
Twenty Nineteen 2.1
Twenty Twenty 1.8
Twenty Twenty-One 1.4
Try switching to the default theme, deactivating all plugins excluding Contact Form 7, Akismet Anti-Spam, Classic Editor and WordPress Importer, and clearing all cache data.
Why you are advised to deactivate plugins and switch to the default theme.
Thanks.
Error Found in Plug-In
Change font size and color 1.0.0
only this – try!
