Laravel Passport & nuxt.js & nginx - oAuth not working - laravel

Question

I'm running a static built nuxt.js app on my server. It uses the nuxt auth module for authentificating against my laravel backend which runs laravel passport.
My auth-strategy looks like this:
auth: {
strategies: {
'laravel.passport': {
url: 'https://correct_url',
//client_id: 1, //for local use
//client_secret: 'CLIENTSECRET1', //for local use
client_id: 2,
client_secret: 'CLIENTSECRET2',
userinfo_endpoint: 'https://correct_url/oauth/me'
}
}
},
In my local environment (yarn run dev) everything runs fine. After I built and deployed my nuxt-app (yarn run build) the authentification process comes to the authorisation step (where I can click "Authorize" or "cancel"). After I click "Authorize" browser redirects to my nuxt-app but requests still give me:
{"message":"Unauthenticated."}
After a few investigations the only possible cause for this could be the nginx-site which is automatically created through laravel forge. Config looks like this:
# FORGE CONFIG (DO NOT REMOVE!)
include forge-conf/correct_url/before/*;
server {
listen 443 ssl http2;
listen [::]:443 ssl http2;
server_name correct_url;
root /home/forge/correct_url/dist;
# FORGE SSL (DO NOT REMOVE!)
ssl_certificate /etc/nginx/ssl/correct_url/589448/server.crt;
ssl_certificate_key /etc/nginx/ssl/correct_url/589448/server.key;
ssl_protocols TLSv1.2;
ssl_ciphers ECDHE-RSA-AES256-GCM-SHA512:DHE-RSA-AES256-GCM-SHA512:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-SHA384;
ssl_prefer_server_ciphers on;
ssl_dhparam /etc/nginx/dhparams.pem;
add_header X-Frame-Options "SAMEORIGIN";
add_header X-XSS-Protection "1; mode=block";
add_header X-Content-Type-Options "nosniff";
index index.html index.htm index.php;
charset utf-8;
# FORGE CONFIG (DO NOT REMOVE!)
include forge-conf/correct_url/server/*;
location / {
try_files $uri $uri/ /index.html;
}
location = /favicon.ico { access_log off; log_not_found off; }
location = /robots.txt { access_log off; log_not_found off; }
access_log off;
error_log /var/log/nginx/correct_url-error.log error;
error_page 404 /index.php;
location ~ \.php$ {
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/var/run/php/php7.2-fpm.sock;
fastcgi_index index.php;
include fastcgi_params;
}
location ~ /\.(?!well-known).* {
deny all;
}
}
# FORGE CONFIG (DO NOT REMOVE!)
include forge-conf/correct_url/after/*;
is there something I overlooked or am I on the wrong path?