Kubernetes nginx ingress cannot find backend service - nginx

Question

I have deployed my API to Kubernetes on AKS through kubectl command from my local machine. But the nginx ingress is not able to resolve the backend endpoint. The ingress logs has an error The service 'hello-world/filter-api' does not have any active endpoint
Steps followed:
Install dapr on AKS
dapr init -k --set global.tag=1.1.2
Install nginx ingress on AKS
helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
helm install ingress-nginx ingress-nginx/ingress-nginx -f ...\dapr\components\dapr-annotations.yaml --set image.tag=1.11.1 -n ingress-nginx
Apply manifest
kubectl apply -f .\services\filter.yaml
What did I try?
Verified the selectors and labels
Followed the steps mentioned Troublshooting nginx ingress
I tried to deploy this to local Kubernetes cluster on windows with docker desktop. This works fine. What am I missing?
filter.yaml
kind: ConfigMap
apiVersion: v1
metadata:
name: filter-cm
namespace: hello-world
labels:
app: hello-world
service: filter
data:
ASPNETCORE_ENVIRONMENT: Development
ASPNETCORE_URLS: http://0.0.0.0:80
PATH_BASE: /filter
PORT: "80"
---
kind: Deployment
apiVersion: apps/v1
metadata:
name: filter
namespace: hello-world
labels:
app: hello-world
service: filter
spec:
replicas: 1
selector:
matchLabels:
service: filter
template:
metadata:
labels:
app: hello-world
service: filter
annotations:
dapr.io/enabled: "true"
dapr.io/app-id: "filter-api"
dapr.io/app-port: "80"
dapr.io/config: "dapr-config"
spec:
containers:
- name: filter-api
image: client/hello-world-filter-api:0.0.1
imagePullPolicy: IfNotPresent
ports:
- containerPort: 80
protocol: TCP
envFrom:
- configMapRef:
name: filter-cm
imagePullSecrets:
- name: regcred
---
apiVersion: v1
kind: Service
metadata:
name: filter-api
namespace: hello-world
labels:
app: hello-world
service: filter
spec:
type: NodePort
ports:
- port: 80
targetPort: 80
nodePort: 30001
protocol: TCP
name: http
selector:
service: filter
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: filter-ingress
namespace: hello-world
labels:
app: hello-world
service: filter
spec:
rules:
- http:
paths:
- path: /filter
pathType: Prefix
backend:
service:
name: filter-api
port:
number: 80

Answer 1

In the service selector, use matchLabels for the service to find the backend pods
example:
selector:
matchLabels:
service: filter