manifest for confluentinc/cp-zookeeper:7.3.x-latest not found: manifest unknown: manifest unknown

While attempting to complete the lab for multiregion https://github.com/confluentinc/examples/tree/7.3.0-post/multiregion the following errors are seen when the command "./scripts/build_docker_images.sh" is executed:

training@training:~/examples/multiregion$ ./scripts/build_docker_images.sh

Build custom cp-zookeeper and cp-server images with 'tc' installed
Sending build context to Docker daemon 1.426MB
Step 1/11 : ARG REPOSITORY
Step 2/11 : ARG IMAGE
Step 3/11 : ARG CP_VERSION
Step 4/11 : FROM $REPOSITORY/$IMAGE:$CP_VERSION
manifest for confluentinc/cp-zookeeper:7.3.x-latest not found: manifest unknown: manifest unknown
Docker image localbuild/cp-zookeeper-tc:7.3.x-latest not found. Please troubleshoot and rerun