IBM Cloud Code Engine does not have authorization to pull an image from its own registry – Docker

I’m pretty new to IBM Cloud and Code Engine. I am trying to deploy an app called "project1" by uploading a docker container to IBM Cloud Container Registry and using it for a Code Engine application.

The problem is, the app creation always fails with this message (the namespace is project_namespace):

"Revision "project1-00001" failed with message: Unable to fetch image "icr.io/project1_namespace/project1": failed to resolve image to digest: GET https:/. See https://ibm.biz/BdPKqq; Authorization required. See https://ibm.biz/BdPKqq."

or sometimes this message:

"Revision "project1-00001" failed with message: Unable to fetch image "icr.io/project1_namespace/project1": failed to resolve image to digest: GET https://icr.io/oauth/token?scope=repository%!A(MISSING)project1_namespace%!F(MISSING)project1%!A(MISSING)pull&service=registry: UNAUTHORIZED: Authorization required. See https://ibm.biz/BdPKqq; Authorization required. See https://ibm.biz/BdPKqq."

I don’t understand why authentication would be failing here. Here is what I do:

ibmcloud login
ibmcloud cr login

docker build -t $DOCKER_IMAGE_NAME $DOCKERFILE_PATH 

ibmcloud target -g $RESOURCE_GROUP_NAME
ibmcloud cr namespace-add $REGISTRY_NAMESPACE
ibmcloud ce project create --name project1
ibmcloud ce project select -n project1

docker tag $DOCKER_IMAGE_NAME icr.io/$REGISTRY_NAMESPACE/${DOCKER_IMAGE_NAME}:latest
docker push icr.io/$REGISTRY_NAMESPACE/${DOCKER_IMAGE_NAME}:latest

ibmcloud ce app create --name $CODE_ENGINE_APP_NAME --image icr.io/$REGISTRY_NAMESPACE/$DOCKER_IMAGE_NAME

Code Engine application should pull the icr.io image sucessfully. Right?