If you are authenticating when pulling Docker images and receive an unauthorized error like the following on your "Spin up environment" step:
It means the username or password you are passing for authentication is incorrect. If you are passing them in as environment variables like the following:
jobs: build: docker: - image: circleci/android:api-29-node auth: username: $DOCKER_HUB_USERNAME password: $DOCKER_HUB_PASSWORD
You will want to ensure they are correct in your project or context variable settings. Docker Hub allows you to create and utilize access tokens, so if you are using one of those it could be it was disabled or deleted a new one will need to be set.