Ispconfig 3.1.13 Nginx HSTS not working

Hey, i use Ubuntu 18.04 with Ispconfig (newest) and Nginx.
I insert
add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
in the Options tab on my domain under additional nginx directives, but if i test it on hstspreload.org it tells me

Code:

The max-age must be at least 31536000 seconds (≈ 1 year), but the header currently only has max-age=0. If you are trying to remove this domain from the preload list, please visit https://hstspreload.org/removal/

but i set it to max-age=31536000?

Can anyone help me?

 

You need preload. Try:

Code:

add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" always;

Restart nginx if necessary.

 

Not work

Code:

Error: Max-age is 0
The max-age must be at least 31536000 seconds (≈ 1 year), but the header currently only has max-age=0. If you are trying to remove this domain from the preload list, please visit https://hstspreload.org/removal/
Warning: Unnecessary HSTS header over HTTP
The HTTP page at http://example.de sends an HSTS header. This has no effect over HTTP, and should be removed

I Think i do anything wrong

 

The Line is in the vhost in /etc/nginx/sites-available
And yeah i use a cms, how Can i Check what in the CMS overrides the nginx value

 

Hey, i asked the author of the cms i use, and he answerd me the cms dont override the HSTS Value

 

I figured it out, it was cloudflare
It override my value