unauthorized: access to the requested resource is not authorized while pushing or pulling images to Quay

Issue

• Unable to push or pull container images after successful login to Quay Enterprise or Quay.io and encounter following error message:

# docker push quay.example.com/username/hello-world
The push refers to a repository [quay.example.com/user/hello-world]
5f345c98fcb2: Waiting 
ff986b10a018: Waiting 
unauthorized: access to the requested resource is not authorized

• Login to Quay fails with following error

# docker login -u quay https://{quayhostname}
Password:
Error response from daemon: Get https://{quayhostname}/v1/users/: EOF

• While installing Quay Operator in OCP 4.3 , noticed all the pods were created except the Quay pod. Pod description throws following error:

Normal   Pulling    21s (x4 over 109s)  kubelet, ip-example1.us-east-2.compute.internal  Pulling image "quay.io/redhat/quay:v3.2.0"
  Warning  Failed     21s (x4 over 109s)  kubelet, ip-example1.us-east-2.compute.internal  Failed to pull image "quay.io/redhat/quay:v3.2.0": rpc error: code = Unknown desc = Error reading manifest v3.2.0 in quay.io/redhat/quay: unauthorized: access to the requested resource is not authorized
  Warning  Failed     21s (x4 over 109s)  kubelet, ip-example1.us-east-2.compute.internal  Error: ErrImagePull
  Warning  Failed     9s (x7 over 108s)   kubelet, ip-example1.us-east-2.compute.internal  Error: ImagePullBackOff