Some unused, legacy or deprecated tags were cleaned up today from docker registries, most notably dolfinx/dolfinx:latest and dolfinx/lab:latest.
The latest tags was deprecated more than a year ago, and since then up to date images have been pushed to dolfinx/dolfinx:nightly (dolfinx/lab:nightly, respectively) for development version or dolfinx/dolfinx:stable (dolfinx/lab:stable, respectively) for the latest release, while dolfinx/dolfinx:latest (dolfinx/lab:latest, respectively) stopped receiving any updates.
If you are suddenly getting errors like
Error response from daemon: manifest for dolfinx/dolfinx:latest not found: manifest unknown: manifest unknown
chances are that you should update your docker file, installation script or CI script, by choosing either a nightly or stable tag.