Ruby on Rails app in kubernetes with ingress-nginx isn't serving static files

Question

I have Ruby on Rails app with admin dashboard hosting on Kubernetes. I already have bundle exec rake assets:precompile and ENV RAILS_SERVE_STATIC_FILES true in Dockerfile. I see assets on the server but they are empty :

My ingress:

    apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    kubernetes.io/ingress.class: nginx
    meta.helm.sh/release-name: dev-api
    meta.helm.sh/release-namespace: dev
    nginx.ingress.kubernetes.io/cors-allow-credentials: "true"
    nginx.ingress.kubernetes.io/cors-allow-headers: DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Authorization,X-Authentication-Chain,Source,X-Owner
    nginx.ingress.kubernetes.io/cors-allow-methods: GET, POST, PUT, DELETE, OPTIONS
    nginx.ingress.kubernetes.io/cors-allow-origin: '*'
    nginx.ingress.kubernetes.io/cors-max-age: "3600"
    nginx.ingress.kubernetes.io/enable-cors: "true"
  generation: 6
  labels:
    app: dev-api
   app.kubernetes.io/managed-by: Helm
    chart: api-1.0.0
    heritage: Helm
    release: api
  name: dev-api
  namespace: dev-space
spec:
  rules:
  - host: dev.example.com
    http:
      paths:
      - backend:
          service:
            name: dev-api
            port:
              number: 8080
        path: /api/v1
        pathType: Prefix
      - backend:
          service:
        name: dev-api
        port:
          number: 8080
    path: /admin
    pathType: Prefix

upd:

FROM ruby:3.0.3

RUN mkdir /backend
WORKDIR /backend

RUN apt-get update -qq && apt-get install -y build-essential libpq-dev 
ENV RAILS_ENV production
ENV RAILS_SERVE_STATIC_FILES true 
ENV RAILS_LOG_TO_STDOUT true


COPY Gemfile /backend/Gemfile
COPY Gemfile.lock /backend/Gemfile.lock


RUN gem install bundler -v 2.2.32

RUN bundle install

COPY . ./

EXPOSE 3001

# Start the puma server
RUN bundle exec rake assets:precompile

CMD bundle exec puma -p 3001

I think it's the wrong nginx configuration, but various manipulations with it did not bring results. Maybe you should try to take assets from some storage?