Issues uploading Docker images to a Kubernetes-hosted GitLab instance

I have a GitLab instance running on my Kubernetes cluster, unfortunately, I have issues uploading images to the integrated Docker registry. When I looked into the logs for the Registry pods, I’ve seen messages like this:

time="2020-12-14T14:00:29Z" level=error msg="blob unknown to registry" auth_user_name=shield code=BLOB_UNKNOWN correlation_id=zJXwGLxjiB8 detail="sha256:718b8d69d158fc7af87e5c98047830c2c93fb1df2228e37182a79282cbaf0cf6" error="blob unknown: blob unknown to registry" go_version=go1.14.5 vars_digest="sha256:718b8d69d158fc7af87e5c98047830c2c93fb1df2228e37182a79282cbaf0cf6" vars_name=[grp]/[subgrp]/[project]

I copied the commands straight out of the Registry page in GitLab.