CORS: Preflight Missing Allow Origin Header - php

Question

I am using nginx with PHP and Vue. I`m struggling with CORS error like in a title. I can make normal Fetch requests, however when i want to make some application error from backend (for example, when someone want to create a account, and login is already taken). Im getting Error like in title:
Fetch failed and latern in Network Tab in Dev Tools:
CORS: Preflight Missing Allow Origin Header
Here is my nginx.conf:
server {
listen 80 default_server;
listen [::]:80 default_server;
server_name _;
server_tokens off;
root /app/;
index index.php;
add_header "Access-Control-Allow-Origin" *;
add_header "Access-Control-Allow-Headers" *;
location / {
try_files $uri $uri/ /index.php$is_args$args;
}
location ~ \.php$ {
include fastcgi_params;
fastcgi_pass php:9000;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
}
}
Way i try to send error:
header("HTTP/1.0 460 Aplication Error");
header("Content-Type: application/json");
json_encode($error);
Am i trying to do in proper way at all?
PS Update, i cant change this header, when using calling it by fetch from Vue CLI Server, when i call it directly for example in browser it works correctly