Receive 403 Forbidden from Keycloak on localhost:3000?

Hi all

I am building a web app based on ReactJS and it is running during the bulding process on the http://localhost:3000. For security reason, all backend and web apps are protected through Keycloak.
At the moment, Keycloak and backend service account are running on the Kubernetes cluster as you can see on the picture below:

enter image description here

The web app is also procected through Keycloak and it is running on http://localhost:3000. So, when I start the web app, it redirects me to the login page of the Keycloak. After the successfull login, it redirects back to the web app. Afterwards, the web app makes a request to the backend service and I receive the return http code 403.

Do I receive the return code 403 because of http protocol instead of https?
Or what am I doing wrong?


Here is the overview of the request and response:
enter image description here

I forgot to mention that I have one more web app running on the kubernetes and it also makes a request to backend service account. This works like a charm.