I have created a new reserved static IP in my GCP. See the screenshot marker 1. However my ingress resource is still using the generated ip (screenshot marker 2.)

In the Ingress' YAML file you can see I annotated the static-ip name.

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  annotations:
    ingress.kubernetes.io/backends: '{"k8s-be-31465--b5c10175cf4f125b":"HEALTHY"}'
    ingress.kubernetes.io/forwarding-rule: k8s-fw-default-teamcity--b5c10175cf4f125b
    ingress.kubernetes.io/target-proxy: k8s-tp-default-teamcity--b5c10175cf4f125b
    ingress.kubernetes.io/url-map: k8s-um-default-teamcity--b5c10175cf4f125b
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"extensions/v1beta1","kind":"Ingress","metadata":{"annotations":{"kubernetes.io/ingress.global-static-ip-name":"teamcity-static-ip"},"name":"teamcity","namespace":"default"},"spec":{"backend":{"serviceName":"teamcity","servicePort":8111}}}
    kubernetes.io/ingress.global-static-ip-name: teamcity-static-ip
  creationTimestamp: "2019-11-12T13:57:41Z"
  generation: 1
  name: teamcity
  namespace: default
  resourceVersion: "3433973"
  selfLink: /apis/extensions/v1beta1/namespaces/default/ingresses/teamcity
  uid: 6484482e-0554-11ea-af7d-42010a8400aa
spec:
  backend:
    serviceName: teamcity
    servicePort: 8111
status:
  loadBalancer:
    ingress:
    - ip: 35.190.86.15

That's why I am confused why it is not assigning it to the Ingress resource as expected.