CORS with NGINX Reverse Proxy

Hi All,
I have a VM with nginx installed and it manages the host
Moreover I have a cluster with Rancher reachable at
What I want to obatin is to reach the Rancher cluster through the nginx.
So I want to call rancherproxy and this call must be redirect to rancher.

I attached the nginx configuration

At the same time I’ve customized the ingress rancher with this annotations: "true" PUT, GET, POST, PATCH, OPTIONS rancherproxy "true"

Now If I open my browser at rancherproxy URL I can see correctly the Rancher login page, but when I tried to put my credentials and click-on I stay stucked on the loging page.
I tried to investigate the issue using the developer mode and I saw:

Request URL:

Referrer Policy:
** strict-origin-when-cross-origin**

I don’t know why, I already set the CORS both on nginx and kubernetes ingress

What shoul I do?