Nginx.ingress.kubernetes.io/proxy-body-size not working

Rancher 2.x
1

I want to increase size of post body of each request in Ingress. So I add the

nginx.ingress.kubernetes.io/proxy-body-size: 8m

in yaml file ingress(in view/edit yaml file of rancher) but it doesn’t work. When I get the describe of ingress with kubectl I dont see the added annotation but i see the new added mapping.
Hereis the configs:

YAML file:

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  annotations:
    ingress.kubernetes.io/configuration-snippet: |-
      set $test_host "testdms.test.com"
      if ($host == $test_host) {
        return 301 $scheme://$test_host/webui/;
      }
    nginx.ingress.kubernetes.io/proxy-body-size: 8m
  creationTimestamp: 2018-09-11T12:19:02Z
  generation: 116
  name: test-dms
  namespace: test-dms
  resourceVersion: "95490045"
  selfLink: /apis/extensions/v1beta1/namespaces/test-dms/ingresses/test-dms
  uid: de7c4c1b-b5bc-11e8-84c0-005056bf6431
spec:
  rules:
  - host: testdms.test.com
    http:
      paths:
      - backend:
          serviceName: ingress-e5a45b0dc688c653b79d4b5942ebbe7c
          servicePort: 80
        path: /test
status:
  loadBalancer:
    ingress:
    - {}
    - ip: 198.100.101.171
    - ip: 198.100.101.172
    - ip: 198.100.101.173
    - ip: 198.100.101.61

describe result:

Annotations:
  configuration-snippet:  set $test_host "testdms.test.com"
if ($host == $test_host) {
  return 301 $scheme://$test_host/webui/;
}
Events:
  Type    Reason  Age                       From                      Message
  ----    ------  ----                      ----                      -------
  Normal  UPDATE  36s (x38 over 2h)         nginx-ingress-controller  Ingress test-dms/test-dms
  Normal  UPDATE  21s (x47 over 23d)        nginx-ingress-controller  Ingress test-dms/test-dms
  Normal  UPDATE  <invalid> (x47 over 23d)  nginx-ingress-controller  Ingress test-dms/test-dms
  Normal  UPDATE  <invalid> (x84 over 64d)  nginx-ingress-controller  Ingress test-dms/test-dms
  Normal  UPDATE  <invalid> (x39 over 12d)  nginx-ingress-controller  Ingress test-dms/test-dms